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BCC
16th September 2015, 04:01 PM
My apologies if this has been covered but a search didn't show anything.

I have a Cougar 400 EVS lathe which is all very nice however, it has become apparent that when I run the lathe, the ADSL2 connection to the internet is disconnected. This was sadly discovered during my son's online Uni exam :(. I know it causes strong interference with the AM radio but this new discovery surprised me. Have others experienced such a thing and is there a work around?

Thanks,
Bruce

Yanis
16th September 2015, 04:43 PM
Hmmmm.... pretty dodgy. First question, how far is it from the modem?

The reason I ask is that there are two ways to get interference from electrical appliances. The first is through your power wiring and the second is through the aether. If your appliance is really bad both.

If the lathe is a long physical distance from the modem then it is interference over the power wiring. There are several things you can do to address this.

First place the lathe on a different circuit to the modem. If you have multiple phases aven better but on different circuit breakers will help.

Next use an interference suppression power board for the modem, and maybe also for the lathe. What this does is puts a small RF filter in the power line which stops the interfering signals getting from the lathe to your power wiring (if you put the board on the lathe side) and stops interference from the power wiring getting into the modem. You can get these from most supermarkets and Bunnings. Do NOT go to HN or the good guys. The Monster brand is overpriced junk. Trust me - my wife got one as a "bonus" with our net TV and after it stopped working I took it apart. It was well up to the standard of cheap Chinese junk ebay quality. It was a failure waiting to happen.

Make sure the phone line does not run near the lathe or near the power wiring from the lathe.

That just about covers the power interference. As for the over the air interference there is not much you can do about that other than keeping both the phone line and the modem as far as physically possible from the lathe.

If you are good at engineering then you could use an earthed metal enclosure for the speed control which is most likely where the interference is coming from. However you may also need to enclose the motor if it does not have a metal case but you have to take air flow into consideration.

Good luck in any case. Interference can be a pesky problem, even for experts.

John

Yanis
16th September 2015, 04:48 PM
I should also add that if it is fairly new then it sounds like it may not pass the RFI emission standards in which case you may be eligible for repair, replacement or refund. I am not up with the latest legislation but first contact the reseller and if you get no joy there then contact the ACCC who can advise you.

BCC
16th September 2015, 05:00 PM
Thanks Yanis for your comprehensive answer. Physically the lathe and modem are about 18m and lots of walls apart (only 1 brick wall though). I'm not sure if they're on the same power point circuit. I will look into the suppression power board at first. The lathe is just 1 year old from new but I'm about 300km from the shop so that's a bit of a problem. I will call them and ask anyway.

Cheers,
Bruce

Sawdust Maker
16th September 2015, 07:55 PM
Interesting question
My SWMBO asked me on the weekend if the dusty could effect the efficacy of the internet connection
I suggested it was unlikely, then I wondered whether the DVR could have an impact
I thought it was unlikely as they are on different circuits (shed has it's own) and it is quite some distance from the modem (but then again the modem is a cheap and nasty)

BobL
16th September 2015, 08:59 PM
I have 9 machines on variable speed drives in my shed and they put out a fair RF hash as heard on the AM radio that was in my shed.
This was addressed by getting a digital radio but I was so worried it might upset the neighbours that I did check the level of AM interference outside the shed and found it was barely detectable outside the shed which is clad in metal - some of it is a double skin of metal.

I suspect the noise is coming down the power line so Yanis's tips should work for you there.
If you have an easily accessible 12V car battery and the modem runs on 12V you could try using that and see if it still drops out.

Is it the wireless connections or the whole ADSL connection - have you tried with an ethernet cable from PC direct to the modem?

BCC
16th September 2015, 10:18 PM
Good point, it certainly kills the wireless but I haven't tried the cable connected PC. I will try that once my son's uni assignment is finished :)

Bruce

pjt
16th September 2015, 10:45 PM
My VSDs give the am radio a lot of interference, no issues with the internet as yet, all computer gadgets are plugged into a surge protector board, whether there is some filtering in there as well I don't know.

The solution (or so my instructions tell me) to the am radio interference is the correct type of the cable from the VSD to the motor and all control wiring, the cabling has a layer of woven metal (steel?) strands and will be earthed at the VSD and at the motor.



Pete

Glenn.Visca
16th September 2015, 11:05 PM
Big question here ...

Does your router to internet connection drop ? Or your device to router connection ?... Which I think you indicated was wireless.

802.11a/b/g/n use 2.4ghz.

In the early days of wireless, it was quite common for EM interference to clobber a connection. Things like microwave ovens were notorious.

If its WiFi session drop you are suffering a newer 802.11ac router may (stress MAY) help.

I will do a little research and if I find anything, will let you know.

Have you tried changing WiFi channel ?

Mobyturns
17th September 2015, 08:04 AM
Interesting subjects "electro magnetic interference" (EMI) & "electro magnetic compatibility" EMC - and a very important topics for turners who have implanted medical devices such as defibrillators & pacemakers.

One could say it is a matter very close to my heart :rolleyes: as I have a defib/pacemaker so I am very aware of EMI & EMC and potential risks from "normally operating" and "faulty" equipment.

Medical device manufacturers and medical/cardiac specialists issue warnings and cautions to patients about the potential risks to their medical devices from EMI and what they consider to be "high risk" tasks, tools, machinery etc.

If it is reasonably proven that the lathe or any device is creating interference to other electronic devices it would be prudent to report it to the Australian Communications and Media Authority (ACMA) as they are the body responsible for managing EMI compliance in Australia.

Under Australian legislation electrical/electronic devices are classified as low/medium/high risk devices. Medium level devices include switched & microprocessor controlled motors on lathes; high level devices include welders etc, Both med/high have potential to cause EMI and must conform with standards for EMC. http://www.acma.gov.au/Industry/Suppliers/Equipment-regulation/EMC-Electromagnetic-compatibility/electromagnetic-compatibility-emc-compliance-labelling

"Suppliers" (manufacturer & or importer) must ensure that they certify that their devices comply with EMC requirements by testing equipment, applying for registration of compliance, marking tools/machinery etc with the appropriate compliance mark & keeping records - http://www.acma.gov.au/Industry/Suppliers/Supplier-resources/Supplier-overview/compliance-marks

LukaWoodie
17th September 2015, 10:37 AM
I would consider adding a dV/dt or sine filter to the feed and motor side of the VSD.

Sent from my SM-G900I using Tapatalk

Old Croc
17th September 2015, 08:18 PM
Bruce, you may want to repost this in the Electronics section of the Forum as there are some really cluey guys over there that may not read it here in Wood turning.
Rgds,
Crocy.

BCC
21st September 2015, 11:07 AM
Hi,

I have posted this in the Electronics section as suggested. Just as a follow up to the questions and suggestions:

I have since tested things a bit more and found that the internet connection is momentarily cut when I start the lathe (just like turning the power off to the modem) but it then restores the connection in the next minute even though the lathe is still running. Both WiFi and internet cable services are effected. I have tried using a surge protector at the lathe end and then at the modem end but this has not helped. The surge protector is a Belkin BV104020au2M but I don't know if this is a low quality one or not. Pardon my ignorance but is this the same thing as an "interference suppression power board"? The modem is a TP-Link N600.

Thanks,
Bruce

Yanis
21st September 2015, 12:06 PM
Hi,

The surge protector is a Belkin BV104020au2M but I don't know if this is a low quality one or not. Pardon my ignorance but is this the same thing as an "interference suppression power board" as suggested on the other forum? The modem is a TP-Link N600.

Thanks,
Bruce

OK this device does surge protection (flattens out spikes which can destroy some equipment) and filtration which was what I was talking about.

Form your update it seems to me that there are two possibilities. The first is a "brown out" which is a momentary drop in mains voltage due to the start up current on the lathe motor. This may be caused by a wiring fault coupled with the high start up current on the motor. Or just a long power run from the fuse box to the appliances such as the motor and the modem. There is an easy way to test this. Grab a table lamp and put in one of the old fashioned incandescent lights. CFLs or LED lights are no good for this test. First plug in the light to the same power point (using a double adapter or power board) as you lathe and start the lathe. You should see the light noticeably dim as your lathe starts. If it does move the light to the power point where the modem is then get someone to start the lathe while you watch the light. If it shows the same dimming as you start the lathe then this could be the cause. Now modern power supplies are designed so that they should be able to cope with this but if the unit is getting oldish then it may have developed a fault and be dropping out when you get a small voltage drop as you start the lathe motor. If this is the case then get a replacement plug pack for the modem (or a ne modem). The plug pack are usually 12V at about 1 amp but take it into Jaycar who can supply a replacement plug pack.

The second option is that as the controler circuit starts it is generating some serious hash. In this case my previous recommendations still apply. It may be that the surge protection is not filtering the actual interference. It gets somewhat confusing at this stage but the type of interference that will produce noise on AM radio is different to what would interfere with a modem signal.

You can test whether the devices are on the same circuit bu flipping breakers in your power board.

John

BobL
21st September 2015, 12:07 PM
Hi,

I have posted this in the Electronics section as suggested. Just as a follow up to the questions and suggestions:

I have since tested things a bit more and found that the internet connection is momentarily cut when I start the lathe (just like turning the power off to the modem) but it then restores the connection in the next minute even though the lathe is still running. Both WiFi and internet cable services are effected. I have tried using a surge protector at the lathe end and then at the modem end but this has not helped. The surge protector is a Belkin BV104020au2M but I don't know if this is a low quality one or not. Pardon my ignorance but is this the same thing as an "interference suppression power board"? The modem is a TP-Link N600.

Thanks,
Bruce

No they are different - the surge protects against a large INPUT increase in Amplitude or voltage from the supply, a interference suppression power board prevents transmission of high frequencies back long the power lines.

The fact that drop out only happens when the lathe starts suggests its motor induces large voltage drop on the power line - have you checked if the lathe and modern are on the same circuit?
If this is the problem then neither of the above will fix the problem.

A soft start device would eliminate the V drop. I don't know if this is compatible with your EVS system
Most generic variable speed power supplies provide soft start as a programmable standard - sounds like another good reason to get a VFD.

Yanis
21st September 2015, 12:34 PM
It just occurred to be that there may be an easy way to test the brown out theory.

Get someone to watch the modem while you start the lathe. If all of the leds (including the power led) go out when you start the lathe then the modem is actually loosing power. This means that your power pack is resetting. In this case a new power pack may do the trick as in my previous post.

Yanis
21st September 2015, 02:34 PM
No they are different - the surge protects against a large INPUT increase in Amplitude or voltage from the supply, a interference suppression power board prevents transmission of high frequencies back long the power lines.

Correct they are but if you look at the actual product description on their web site it does both.



The fact that drop out only happens when the lathe starts suggests its motor induces large voltage drop on the power line - have you checked if the lathe and modern are on the same circuit?
If this is the problem then neither of the above will fix the problem.


I agree. But most modern plug packs are designed for a very wide voltage range so as per my previous post it is most likely a combination of voltage drop with dodgy plug pack.

I suspect that a replacement plug pack will do the trick.

I checked the specs and it is 12V at 1.5 A so this one should do the trick. Just select the correct polarity and connector for your modem.

http://www.jaycar.com.au/Power-Products-Electrical/Plugpacks/DC-Output/Switchmode-Plugpack-9VDC-1-66A/p/MP3484

John

westom
21st September 2015, 11:04 PM
I have since tested things a bit more and found that the internet connection is momentarily cut when I start the lathe (just like turning the power off to the modem) but it then restores the connection in the next minute even though the lathe is still running. Both WiFi and internet cable services are effected.
First, a surge protector is completely useless. That protector does nothing until 230 volts well exceeds 500 volts. EMI/EMC/RFI is typically single digit or low tens of volts.

Second, best interference solutions are implemented at the source. A simplest start is an AC line filter at each lathe - for constant noise. A snubber on the lathe power switch may also help (for switched noise). If any lathe interferes with an AM radio, then the problem must be solved at the source.

Third, phone lines should be twisted pair. Today many use CAT5 cables for a phone line. Overkill. Twisted pair means no 'over the air' interference.

Fourth, all earth grounds must be inspected. Do not confuse earth ground and safety ground. Both are interconnected and are electrically different.

Your incoming phone line (if up to current international standards) would have a protector when the telco's wires meet yours. And within meters of an earth ground also used by AC electric. This earth ground serves many purposes including elimination of spikes that would otherwise connect directly from AC wires (even AC ground wires) into the telco and cable TV wires.

Fifth, power supplies in electronics are so robust that noise on AC wires should not cause problems. However, safety ground and signal wires are more susceptible to interference; another potential path for interference signals.

And finally, an AM radio test should be conducted while receiving a station that is maybe 70 km distant (rather weak signal). If equipment is working properly, then even a signal that weak should not suffer interference.

BTW, ADSL is a radio wave on the phone line. Most probable is radio waves from the lathe are at same frequencies. Most likely path of that interference is from the lath into ADSL and cable wires. Somehow that signal may be connecting from the lathe AC electric directly into those signal wires. Improper grounding (as discussed earlier) would explain that direct connection.

Evanism
22nd September 2015, 02:18 AM
I would just go buy a few RF chokes from Amazon: http://www.amazon.com/gp/product/B007Q94CJS

Put them on everything.

westom
22nd September 2015, 03:57 AM
I would just go buy a few RF chokes from Amazon: http://www.amazon.com/gp/product/B007Q94CJS

Put them on everything. Recommendations without numbers indicate speculation. Those RF chokes are for frequencies well about 1 Mhz (ie above AM radio frequencies). Those chokes do not do what AC line filters do. That superior solution - especially for lower and more relevant frequencies - is an AC line filter.

Chokes also would not address a transient spike created by a switch. A recommended snubber addresses that noise at the source. Again, best solution address a problem at the source - not its symptoms.

Evanism
22nd September 2015, 12:09 PM
Hmmm. Ok. It's a valid point about speculation.... But, regardless these RF chokes do exactly what I say. On the power cables of the machines, put one at the top, another at the bottom.

The advice above about earthing is dead on, so is the advice of getting a simple filter for the ADSL line.

If one speaks to an Internet tech at a "yum cha" computer parts store, they will sell you 4 or 6 of these chokes and tell you to put them on the modem power lines and those of the machines causing noise. This will do nothing about AM radio interference or your microwave causing outages in the 2.4 band, but it's a 2 minute $5 solution that works.

This solution solves the OPs request of "my lathe stuffs the ADSL, make it stop".

westom
22nd September 2015, 02:23 PM
The advice above about earthing is dead on, so is the advice of getting a simple filter for the ADSL line. AN ADSL line must not be filtered. Filtering only reduces ADSL signals. Any line branching off the ADSL line must be filtered so that an ADSL signal never sees those branch circuits. But an ADSL line must have no filters between a modem and its internet provider's DSLAM.

Meanwhile, an ADSL signal has less noise when its wire is twisted pair (ie CAT5).

Better than multiple ferrite chokes is one AC line filter located as close to the lathe as possible. An effective filter (choke) must also eliminate AM radio interference to fully eliminate ADSL interference.
Some examples for various single digit amp loads:
http://www.ebay.com.au/itm/2pcs-7012R0-EMIFIL-AC-LINE-FILTER-Common-Mode-Choke-2-0-AMP-CH-RADIAL-2A-0-7mH-/121438232207
http://www.digikey.com.au/product-search/en?mpart=EH24-3.0-02-1M2&vendor=817
http://www.digikey.com.au/product-search/en/filters/power-line-filter-modules/3408328?k=corcom

BCC
22nd September 2015, 03:00 PM
Thanks Westom for your comprehensive contribution. I'm not very electrically confident so I don't know how an AC line filter would be fitted. Once that cable goes into the lathe I wouldn't have a clue what to connect to what. The ground wire on the house seems quite solid but I don't know the difference between an earth ground and a safety ground. When you refer to improper grounding, are you referring to inside the lathe or the spike into the ground beside the house?

Evanism, the RF chokes at Jaycar seem to be small electronic pieces which go in a circuit board and look very different to the Amazon link. Do the ones you're suggesting just clip over the cable?

Thanks,
Bruce

westom
22nd September 2015, 03:34 PM
The ground wire on the house seems quite solid but I don't know the difference between an earth ground and a safety ground. When you refer to improper grounding, are you referring to inside the lathe or the spike into the ground beside the house?
Safety ground is a ground prong in the wall receptacle. Its primary purpose is to carry fault currents back the breaker box to trip a circuit breaker - to protect human life.

Earth ground is a wire from breaker box to an earth ground electrode outside.

Safety ground from the lath should connect to the same earth ground that any ADSL protector must also connect to. Either at the breaker box, on an earth ground electrode or at a common point on that interconnection. So that any ground transient from a lathe also connects equally to an ADSL modem and cable TV ground.

If lathe, earth, and ADSL grounds are at same potential, then no (or minimal) noise exists. However, if any of those items connect to a separate earth ground, then noise can be higher.

AC line cord has two power wires that connect to two power pins in the lathe. That filter simply connects two AC power wires to two lathe power pins. So that current on both AC wires passes through the filter just like AC electricity passes through any AC plug. Best place for a line filter is just inside a lathe where AC power enters.

Evanism
22nd September 2015, 04:41 PM
Evanism, the RF chokes at Jaycar seem to be small electronic pieces which go in a circuit board and look very different to the Amazon link. Do the ones you're suggesting just clip over the cable?

Jaycar might not have them. Yes, they clip over your power cord. Try MSY in Fyshwick.

I'm in CBR, nice to find another local turner. The 400 is an awesome lathe. I've a 350 and stoked with it.

I suggest only amazon as if you look at the comments (hundreds of them) they all have the same traumas as you. I'm not discounting the other solutions, but focusing on a quick cheap practical fix. I had 2 houses in Jerra and the ADSL there was terrible (that was back then!).

You could also try a little tiny UPS on the modem, but since the ferrite cores are so cheap, they are really worth a crack.

BCC
22nd September 2015, 05:05 PM
Thanks again to both of you; I will pursue these options and see how things go.

Yes, the internet speed in Jerra is about half that of our last house 20km out of town.

Bruce

Evanism
22nd September 2015, 05:14 PM
That filter simply connects two AC power wires to two lathe power pins. So that current on both AC wires passes through the filter just like AC electricity passes through any AC plug. Best place for a line filter is just inside a lathe where AC power enters.

Do they sell this kind of thing in the US? You just plug a little doodad into the plug end and then the wall? How cool. I'll have to look that up.

Yanis
22nd September 2015, 05:25 PM
Thanks again to both of you; I will pursue these options and see how things go.

Yes, the internet speed in Jerra is about half that of our last house 20km out of town.

Bruce

Be sure to check out if it is resetting the modem due to a voltage drop. Your description sounds suspiciously like it is being reset.

Logon to the modem and check the uptime on the status page. If it is being reset then your uptime should be the time since you last turned on your lathe. Second watch the modem while someone turns on the lathe. if the lights all go out then that confirms my suspicion and it will not be interference.

If it was interference I would expect it to be continuous, not just when you turn it on. It still may be but it sounds more like a brown out rather then interference.

BCC
22nd September 2015, 05:49 PM
Sorry, I forgot to clarify earlier. We tested it last night and it is only the internet connection lights that go out, not the whole lot.
Bruce

Uncle Al
22nd September 2015, 08:46 PM
Just to clarify a couple of items. I also Have a Cougar EVS 400, which has a 2 horsepower 3 phase motor (hence the dimming of lights etc.) driven by a built in VFD, which can be a source of radio interference. As others have said, a great lathe, and mine does interfere with the A M radio, which doesn't really bother me when I am concentrating on turning.
I don't know if there is any problems with modems etc.
Hope you can resolve the problem cheaply.

Alan...

westom
22nd September 2015, 11:32 PM
Just to clarify a couple of items. I also Have a Cougar EVS 400, which has a 2 horsepower 3 phase motor (hence the dimming of lights etc.)
I did not see that. Do you mean dimming of other household lights? That dimming must never happen; an indication of a house wiring problem.

In EMI/EMC/RFI conferences, many engineers are bald. That is not from scratching heads. That is the amount of skill sometimes necessary to solve such problems.

Numerous perspectives (combinations) must be considered. ADSL problems can be incoming on AC mains (mostly low voltage or very high spikes) or via the signal wire (a more common incoming path). At the same time, a lathe must be discussed in terms of the outgoing source (ie AC electric) or some other source (ie other electrical connections).

Filters are needed on the lathe - not ADSL. Those filters should have been in the lathe (as discussed in a recent Electronics Design magazine article). ADSL needs to be less exposed (ie twisted pair wires, common earth ground). ADSL filtering is best ignored. Filters must be on a source; not a victim.

Cited are only some examples of each 'variable'. But somehow interference must have both an incoming electric current path and an outgoing current path through the ADSL modem. Either from noise or from an electric current or signal to noise reduction.

Yes, those many conditions create an exponentially increasing number of reasons for that interference. Scratching your head is normal.

AM radio interference indicates a constant problem AND a design that violates what must be standard in all appliances. Meaning those various types of common mode filters, that are always required, are probably missing.

westom
22nd September 2015, 11:43 PM
Do they sell this kind of thing in the US? You just plug a little doodad into the plug end and then the wall?
Filters must be rated for current. One that can be plugged in must be rated at least 15 or 20 amps. Meaning that filter need be massive, heavy, and expensive. A much better filter (for less current) can be used when part of the noise generator. Those filters must be standard in anything with electronics to meet international design standards. Anytning electronic that interferes with AM radio has a defect - since filters that do not plug-in must already be inside.

Mobyturns
23rd September 2015, 09:46 AM
See my post #10.

To be quite frank I'm becoming concerned about the quality of EMC compliance with the "generic" lathes we see under multiple brand names. This is the main reason I purchased a Vicmarc VL150 recently, much higher confidence in the product & compliance with Australian standards for EMC, and use of quality components etc.

Some of these machines are a "bargain" for a reason - either lower quality components, defacto compliance etc.

Big Shed
23rd September 2015, 10:20 AM
Not all of these Chinese lathes have issues with interference and/or non-compliance though.

I have the Hare & Forbes WL46 and there is zero interference with AM/FM radio in my shed, nor does it interfere with the WiFi connection from my CNC computer.

Yanis
23rd September 2015, 10:21 AM
Sorry, I forgot to clarify earlier. We tested it last night and it is only the internet connection lights that go out, not the whole lot.
Bruce

OK, definitely RFI then but that it is producing enough interference to cause a disconnection is a serious problem. Normally RFI results in an interruption of the data, not a reset of the connection.

Also consider where the phone line is tracking inside the house. If it travels close to the lathe or the mains wiring to the lathe then that can also be an issue.

John

BCC
23rd September 2015, 03:07 PM
The phone outlet that the modem plugs into is about 2m from the main electrical box outside the house. I really don't think I can do much to change that.

Big Shed: Bummer, the WL46 was my other choice at the time.

Mobyturns: At $2,400 (now $2,980) I really didn't think I was buying a cheap alternative to eg the WL46

Bruce

Big Shed
23rd September 2015, 03:29 PM
See my post #10.

To be quite frank I'm becoming concerned about the quality of EMC compliance with the "generic" lathes we see under multiple brand names. This is the main reason I purchased a Vicmarc VL150 recently, much higher confidence in the product & compliance with Australian standards for EMC, and use of quality components etc.

Some of these machines are a "bargain" for a reason - either lower quality components, defacto compliance etc.

Then again, paying top price for anything doesn't automatically mean that one gets top quality and full compliance with the national standards, just ask a Volkswagen owner in the US, or even Volkswagen Golf owners here in Oz.

I have a sneaking suspicion that when buying a Vicmarc lathe even then the electronics may be sourced from China?
I seem to remember that they have their castings done in Thailand?

BobL
23rd September 2015, 04:56 PM
Have you tried starting on slowest speed with no load (not even a chuck) ?

BCC
23rd September 2015, 05:25 PM
BobL, I just tried that and strangely it isn't cutting out the modem at all just now, even with a chuck and partial bowl. I'm sure that intermittent issues are even harder to trace.
Bruce

BobL
23rd September 2015, 05:50 PM
BobL, I just tried that and strangely it isn't cutting out the modem at all just now, even with a chuck and partial bowl. I'm sure that intermittent issues are even harder to trace.
Bruce

I doubt it's an intermittent fault could be a way of diagnosing the source of the problem.

Now try starting with a larger and larger load but always at low speed - it may be a simple work around will be to always start it at low speed - which is actually a sensible thing to do anyway.

A fully programmable VFD should allow you to program soft or slow start for ANY speed.

Mobyturns
23rd September 2015, 09:04 PM
... I have a sneaking suspicion that when buying a Vicmarc lathe even then the electronics may be sourced from China?
I seem to remember that they have their castings done in Thailand?

Country of origin, or price, has nothing to do with it. Compliance with Electro-Magnetic Compatability standards, responsible design and manufacturing quality are the issues.

When we look at the many variants of the generic lathes often we see different specs at quite different retail prices. All of the variants have to comply with our EMC standards if they are to be imported & sold in Australia.

The VW scandal simply highlights the lengths some companies, even respected brands, are willing to go to to retain market share. Hopefully we will now see more effort by regulators to enforce compliance.

BCC
23rd September 2015, 10:28 PM
I have spoken with the retailer and they say they haven't experienced this before. It is a couple of weeks past the one year warranty. I'm not sure how I would prove to them that it is not working correctly regarding EMC standards?

westom
23rd September 2015, 11:02 PM
I'm not sure how I would prove to them that it is not working correctly regarding EMC standards? Anytning electronic that interferes with AM radio has a defect.

Mobyturns
24th September 2015, 07:43 AM
I see two separate issues here,



Line voltage drop - "brown out" - due to the starting current of the electric motor. The voltage drop is causing the dimming of lights, and potentially causing the modem to drop out due to reduced line voltage or transient spikes in power.
electro magnetic interference / radio frequency interference - the radio reception interference. It is most likely there are issues with the electro magnetic compliance (EMC) with the motor / VFD combination.


The voltage drop can be minimized by

having a dedicated circuit for the lathe and running only the lathe on the circuit.
running the dust extractor on another circuit
having a licensed electrician do a safety audit of your premises & advise you on the "brown out" issues.


The 2 hp 3 phase electric motor on the Cougar potentially draws 6 Amps @ 240v (when running normally); a 1 hp dust extractor another 7.3 Amps @ 240v. Both current loads will be momentarily higher when the machines are started, because electric motors require more power to get the shaft up to speed then the required current drops off when they reach motor speed. You may experience a "brown out" if the combined loads exceed the capacity of the "network" to supply.

The capacity of power network is typically designed for something like 4 or 5 kVa per lot depending upon region, age of the installation, distance from transformer etc.

The motor/VFD could also be running "under voltage" due to supply network design, or domestic wiring issues. The dimming of lights should be investigated by a qualified electrician.

Typically the permissible voltage range for a 240v supply in Australia is between "256 to 226 Volts." It is possible that the total loads (Air Cons, washing machine, stove, hot water system etc) in use on your property, at the times you are operating the lathe, are exceeding the design capacity of the supply network or your supply voltage is already in the lower permissible range.

The RFI is best explained by reference to

http://www.acma.gov.au/Industry/Broadcast/Spectrum-for-broadcasting/Spectrum-radio-broadcasting/whats-wrong-with-my-radio-reception

BCC
24th September 2015, 09:49 AM
I think in my case it is option 2. The dimming lights was a different poster, I don't experience that. Also, it isn't all the lights on the modem that go out; only the internet connection ones.

Since yesterday arvo, any time I've checked, the internet hasn't dropped out so I'm trying to figure out what is not switched on at the moment.

westom
24th September 2015, 10:21 AM
Also, it isn't all the lights on the modem that go out; only the internet connection ones. That would be due to the same noise also heard on AM radio. That AM radio is a most powerful diagnostic tool. Since noise that creates AM radio interference also causes a low 'signal to noise' ratio resulting in a loss of ADSL connections.

Use an AM radio (tuned to a distant and weaker station) to find source of that noise and interference.

BobL
24th September 2015, 11:00 AM
All this reminds me of our first (expensive) dishwasher we purchased in 1994 - it run fine for a many years but then it started working very intermittently.
Mostly it would not start and when it did, it would not usually finish a complete cycle.
It's not like the power would go off, all the lights would stay on it would just not proceed in the cycle

Called the serviceman, and would you believe it, for the half hour or so he was there it worked fine and he suggested taking it to the service centre for long term monitoring

At the service centre it ran flawlessly over a couple of days and they said there was nothing wrong with it.
Back home it ran intermittently again
Back at the service centre it ran fine so I brought it home and same problem

A couple of days later I was talking about this to a group at morning coffee and a physics professor said "check the line voltage".
Over a period of a week I noted the dishwasher would work provided the voltage was above a certain V - it was something like 240V.
We removed everything else connected to that circuit and it still did the same thing.
Called their service centre and told them about this and eventually got put through to a senior engineer on the east coast.
The first thing he said is where do you live, when I said Perth he was surprised.
He knew about this problem but only when voltages dropped to around 200V which happened sometimes in the country

Back at the service centre they confirmed their line V was pretty stable around 245V.
To fix the problem would require a new motherboard (it was probably just s simple V regulator) but they would not repair (but replace the motherboard) and it was inside a foam filled door it would cost was ~$250!
As you can imagine having already forked out $$ for a service call I was not happy about it.

I started to take the door apart and realised it was not going to be easy to get it all back together so I left it.
I solved the problem in the short term by borrowing a Variac from work and setting the V to ~250V.
Over the next 12 months the Variac output had to be slowly increased to keep the machine running until it got to about 265V and at that point I decided things were too dangerous and we replaced it