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BobL
7th May 2013, 10:58 PM
My Son wanted something that he could monitor the power consumption of his home server which has 20 hard drives in it so I knocked up the simple extension cord with a built in V/I AC meter. It's only good to 100 mA on the current but that's more than enough for him. I wired a switch in line with the power supply line so the display so it could be turned off when not required.

The panel meter is $8 on ebay (http://www.ebay.com.au/itm/LCD-Digital-AC-Volt-Voltage-Amp-2-1-Panel-Meter-Voltmeter-Ammeter-5-50A-/130737288371?_trksid=p5197.m1992&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D14%26meid%3D7488467137692013648%26pid%3D100015%26prg%3D1006%26rk%3D1%26sd%3D130737288371%26) - I bought 4 more because I will add these to a couple of machines WIGRTI.

Very easy to wire up, just have to cut the active line and pass it through the sensing coil and rejoin it again.
The earth line and the neutral stay intact except the neutral line needs to be exposed to provide a connection to run the meter along with another connection to active.
It could be added to any machine with very little effort.
Here it is monitoring the warm up power drawn by my coffee machine - fortunately the coffee machine has a 8:1 duty cycle so it not always so thirsty on the juice.
http://www.woodworkforums.com/attachment.php?attachmentid=266868&stc=1

Bob Willson
8th May 2013, 11:15 AM
Damn you BobL. Now I have to go and soend more money on eBay. :) :rolleyes:

BobL
8th May 2013, 12:51 PM
Damn you BobL. Now I have to go and soend more money on eBay. :) :rolleyes:

Yeah I've watching this one while I make coffees and dreaming up applications and I reckon these things are going to be really useful.

I was thinking to add these onto some of the power lines of my breaker box and maybe even one to the whole mains switch as they is supposed to be rated to up to 50A.

Come to think of it why aren't these STANDARD on expander boards to save the headache of the damn things tripping out?

Ropetangler
16th May 2013, 11:47 PM
The panel meter is $8 on ebay (http://www.ebay.com.au/itm/LCD-Digital-AC-Volt-Voltage-Amp-2-1-Panel-Meter-Voltmeter-Ammeter-5-50A-/130737288371?_trksid=p5197.m1992&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D14%26meid%3D7488467137692013648%26pid%3D100015%26prg%3D1006%26rk%3D1%26sd%3D130737288371%26) - I bought 4 more because I will add these to a couple of machines WIGRTI.


Hi Bob, what is the meaning of the term WIGRTI? I have looked at acornym finder without any joy and you have made me curious.
Regards'
Rob.

BobL
16th May 2013, 11:53 PM
Hi Bob, what is the meaning of the term WIGRTI? I have looked at acornym finder without any joy and you have made me curious.
Regards'
Rob.

When I get around to it.


What I have got around to doing is adding one of those V/I meters to the switch unit for my DC.
It's very interesting to watch it change when the unit is turned on or various blast gates are opened/closed.
http://www.woodworkforums.com/attachment.php?attachmentid=268219&stc=1

Ropetangler
17th May 2013, 01:04 AM
When I get around to it.


What I have got around to doing is adding one of those V/I meters to the switch unit for my DC.
It's very interesting to watch it change when the unit is turned on or various blast gates are opened/closed.

Ah thanks for my edification, and that is a nice and tidy installation there too. You will probably find that you will be able to tell when it is time to empty your DC and clean/replace your filters by watching the current draw with no dust being conveyed, but the system running.
Actually I am looking for some similar measurement system for my camper trailer, to check the state of batteries and charge rate of a proposed solar panel but as LEDs glow brightly in the dark, I may just settle for old fashioned analogue meters, so as not to disturb our sleep.
Regards,
Rob.

BobL
17th May 2013, 01:23 AM
Ah thanks for my edification, and that is a nice and tidy installation there too. You will probably find that you will be able to tell when it is time to empty your DC and clean/replace your filters by watching the current draw with no dust being conveyed, but the system running.
I'll be monitoring it. A blocked filter is equivalent to all blast gates closed where the current drawn drops as the impeller stalls and is churning rather than transporting air so it does less work. The difference is quite marked. About 9.2 A with all blast gates open and 6.5A with them all closed.


Actually I am looking for some similar measurement system for my camper trailer, to check the state of batteries and charge rate of a proposed solar panel but as LEDs glow brightly in the dark, I may just settle for old fashioned analogue meters, so as not to disturb our sleep.
You will need something for DC (mine are AC) and also might want something a bit more sensitive than 100 mA.

rusel
17th May 2013, 05:47 AM
For those with less skill then bob............... For $20
https://zazz.com.au/daily/thingy/7122

BobL
17th May 2013, 09:44 AM
For those with less skill then bob............... For $20
https://zazz.com.au/daily/thingy/7122

Interesting - already sold out I see - no doubt there are others around.

malb
18th May 2013, 08:33 PM
For anyone near an ALDI, they had their power meter this week at $14.99, and their RF remote switches at (I think) $19.99.