Thread: Dust Extractor help please!

They could have also said it won't work because you asked a question outside the scope of their training/knowledge and rather say so they covered their behinds.

Pete

Originally Posted by QC Inspector

They could have also said it won't work because you asked a question outside the scope of their training/knowledge and rather say so they covered their behinds.

Pete

Sure, that's always a possibility. In saying that, my BS meter is pretty good and GregMach are not just mere retailers. They also design and install pretty serious DE's for commercial applications. The saleman, who I've dealt with many times and AFAIK has yet to BS me , consulted someone from their commercial department who was more experienced and knowledgable. In other words, I have no reason to doubt the information I was told.

Originally Posted by KahoyKutter

I explored the VFD option and according to GregMach, the Laguna's 3 phase motor isn't capable of running at 60Hz.

That's strange because apart from a couple of motors that were about 100 years old every motor I've tested has been able to run at 60Hz. Perhaps he means its a delta 415V and cannot be converted to run on 240V 3P. In that case it would still run at 60Hz on a 3p-3p VFD. I'd really like to see the name plat on the motor.

Most resellers don't know much technical stuff about what they selling. I've given up counting the poor or non-existent advice I've heard at tool shops. Occasionally I've even stepped in between a customer and a sales assistant and offered advice . The salespersons reactions have ranged from thanking me, through to walking away in embarrassment.

I've been reminded of this again recently doing the grand tour of tool shops looking at SCMS. One possibility they are saying it won't run on 60Hz is a warranty rather than motor issues. Even though running on a VFD @60HZ should be fine if something goes wrong (even to the motor running on a VFD) they don't want to get into an argument with the manufacture. It reminds me of a mate who bought a new 4WD and a few months later replaced the rims and tyres. When a problem issue came up with the motor the dealer tried to blame the wheels.

Originally Posted by BobL

That's strange because apart from a couple of motors that were about 100 years old every motor I've tested has been able to run at 60Hz. Perhaps he means its a delta 415V and cannot be converted to run on 240V 3P. In that case it would still run at 60Hz on a 3p-3p VFD. I'd really like to see the name plat on the motor.

Hi Bob,

Perhaps I misunderstood the reason given due to my lack of understanding of the technical side of things. Basically I told him that I had 15A SP GPO's in my garage and asked if the 3ph variant of their cyclones could be run @60Hz via a VFD as I had read on this forum it was a way of increasing flow. They knew the reason why I wanted to do this without even asking and he went to talk to his colleague as well as the owner about it. It might be the delta 415V reason you surmised about, but the gist of their response was it either couldn't be done or if it could, it wouldn't provide the improvement that I was looking for. It didn't seem to me that they were simply steering me away from that option due to inconvenience or ignorance. If anything, they seem keen for me to spend more of my money with them (whatever the cost of a suitable VFD + the price difference of the 3ph model).

Originally Posted by KahoyKutter

Hi Bob,

Perhaps I misunderstood the reason given due to my lack of understanding of the technical side of things. Basically I told him that I had 15A SP GPO's in my garage and asked if the 3ph variant of their cyclones could be run @60Hz via a VFD as I had read on this forum it was a way of increasing flow. They knew the reason why I wanted to do this without even asking and he went to talk to his colleague as well as the owner about it. It might be the delta 415V reason you surmised about, but the gist of their response was it either couldn't be done or if it could, it wouldn't provide the improvement that I was looking for. It didn't seem to me that they were simply steering me away from that option due to inconvenience or ignorance. If anything, they seem keen for me to spend more of my money with them (whatever the cost of a suitable VFD + the price difference of the 3ph model).

Which P Flux model did you end up buying and how have you found it?

Originally Posted by RSD

Which P Flux model did you end up buying and how have you found it?

As per my PM reply, I went with the Laguna P Flux 3 but I've yet to take delivery of it. It's in their warehouse, and it's all paid for, I just have to make room for it first. Besides, I'm still waiting for my 6" flex ducting to arrive from Amazon, and GregMach have yet to receive the 8" to three 6" outlet fitting that I ordered with the machine. I plan to get it delivered in a fortnight. Cheers.

other then a slightly bigger bin and hepa filter any reason you chose a Pflux over a Cflux??

Originally Posted by havabeer69

other then a slightly bigger bin and hepa filter any reason you chose a Pflux over a Cflux??

No - the HEPA filter is the attraction given where my unit will be situated

Originally Posted by KahoyKutter

Hi Bob,

Perhaps I misunderstood the reason given due to my lack of understanding of the technical side of things. Basically I told him that I had 15A SP GPO's in my garage and asked if the 3ph variant of their cyclones could be run @60Hz via a VFD as I had read on this forum it was a way of increasing flow. They knew the reason why I wanted to do this without even asking and he went to talk to his colleague as well as the owner about it. It might be the delta 415V reason you surmised about, but the gist of their response was it either couldn't be done or if it could, it wouldn't provide the improvement that I was looking for. It didn't seem to me that they were simply steering me away from that option due to inconvenience or ignorance. If anything, they seem keen for me to spend more of my money with them (whatever the cost of a suitable VFD + the price difference of the 3ph model).

Let's clear this up and remove the confusion or at least attempt to make it less foggy. In dust extraction in AUSTRALIA there are two levels of three phase, one is 240V and one is 415V and the latter is what you get when three phase comes out of a three phase power point in Australia, the former is when three phase is supplied from a VFD that runs from a single phase power point in Australia and both result in a motor speed of 2850RPM. The three phase motor supplied on the Laguna might only be a single voltage motor where motors such as the one that powers a Clearvue can either be used as 3 phase 415V or three phase 240V when configured properly. This is done within the connections on the motor and no motor modifications are needed just a screwdriver. The latter (240V) can only be done through a VFD (not quite true but let's ignore three phase rotaries) so the salesman was right but wrong the way I see it.

The Laguna 3 phase motor may only be a 415V single voltage motor so when plugged into a 415V power point it will have a maximum motor speed of 2850 RPM but a VFD can be used on the 415V circuit to run the motor at whatever speed you want within reason as can the three phase motor working at 240V. I would advise anyone buying a dust extractor to buy a three phase unit no matter what the voltage and use a VFD due to less current start demands and the speed control it gives, Less start current means you can re-start the motor as often as you like but without a VFD the motor could have a limit or re-starts per hour.

Yes, the salesman was right in that a 415V motor without a VFD will cannot be run at 60hz in Australia but using a VFD it can be as the motor will be capable of that speed and most probably more. I run my Clearvue at either 65 or 70hz with no apparent problems and much lower around 40hz at night to avoid the possibility of annoying the neighbours. If the laguna has a dual voltage motor buy a three phase machine and a VFD, you will never regret that at all and run it on 240V with a VFD. I presume you do not have three phase power but if you do the same advice holds, use a VFD to control the motor speed.

I hope that goes some way to clear the fog.

PS: Motor speed is controlled by hertz as a rule 50hz = 2850 rpm, 60hz = 3450 rpm.

Originally Posted by havabeer69

other then a slightly bigger bin and hepa filter any reason you chose a Pflux over a Cflux??

The P flux is supposed to be 12dB quieter. That's quite a significant difference especially in a 2 car garage workshop which is what I have. The P flux is also 19kg heavier. No doubt part of that is due to the bigger drum, doors + sound baffling, but it's also due to extra bracing and possibly thicker sheet metal used. But the HEPA filter and sound baffling is what pushed me towards the P Flux.

Originally Posted by Chris Parks

. . . as can the three phase motor working at 240V. I would advise anyone buying a dust extractor to buy a three phase unit no matter what the voltage and use a VFD . . . .

Before anyone rushes out and buys any 3P 415V DC and attempts to use a 240V VFD on it, just be aware that not all 415V 3P motors are convertible to run on 240V 3P. At least some of the H&F 3P DCs are hard wired as Delta 415V.

While a 3P 415V delta connected motors will run on 240V 3P they will only develop half power so cannot turn any sort of normal impeller for very long. The motors also cannot easily be converted to 240V 3P - basically the motor needs to be completely rewired which will be more expensive than getting a new motor. Converting these to "Star" or "Y" will make them a 690V motor.
BUT
Finding the right motor for a DC is not as straightforward as for most machines that use belts. Some impellers require longer shafts and most use flange mounts.

Bob, I am referring to 415 in and 415 out on a 415V three phase circuit so 240V is not applicable at all. My apologies if that was not clear.