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Chegz
14-02-2012, 09:50 PM
Hi guys,

what safe ways are there of discharging inverter and noise filters boards on air conditioning? I normally just let them discharge by leaving turned off for 'X' amount of time, just curious thanks

Brian_UK
14-02-2012, 10:57 PM
It used to be recommended to discharge them through an electric soldering iron.

But as the manufacturers suggest a time scale and voltage check for discharge I normally follow that.

[edit]
Did a Google on this subject, just loved this page....
http://www.gallawa.com/microtech/safety.html

Grizzly
15-02-2012, 07:35 AM
You are showing your age Brian.
Using a soldering Iron.
Although as a bleed resistance it would make sense.
(hopefully someone does not try this with a cordless version :D)

As to lone man working not being allowed?
Interesting!

Grizzly
Sorry no points this time.GTSTL.

chilliwilly
21-02-2012, 11:26 PM
Just make up a jump lead from a peice of 2.5mm2 multi strand single insulated wire with one end into a terminal of a crocodile clip, and the other end either bare or barrel crimped to a long m4 screw with shrinkband over it. Then just short out the supply and output terminals to each other and then to earth/ground. If you really want to go to town you could connect a 15w rough service pigmy lamp holder in series with the lead if you beleive that an arc will damage components.

I just simply short out the terminals to each other and then to earth/ground with a peice of wire. I've never damaged anything with the small arcing that can be present. Sometimes when the invertor is powered down the changeover to discharge the outputs that takes place on some makes of invertors. Can take longer or not at all as the unit gets older and to be honest I can't be arsed waiting for them to discharge. If the motor is connected in star/wye which is not normally a requirement with invertors, (however if the unit is having problems with high starting torques on older motors I have seen them connected in star on 415v motors). Then you just need to short the outputs to earth/ground.