EMI !!!

Ive almost finished Xen now, and have been giving it a test run. Everything runs fine until I use the saw at the back, then the signal is lost. The problem is its run off a starter motor trigger by a solenoid. Unfortunatly, my attempts to get into the thing to clean it have been unsuccessful as the bolts refuse to budge. Admittedly, I havent fitted ANY suppression yet, although i will be doing tonight (will a 10,000pf capacitor across the terminals do it?) How do i suppress the spark inside the solenoid? and any other tips? All my sensative electronics are inside aluminium boxes.

btw, the starter motor is completely isolated from the shell and chassis as it is mounted on a non-electically-conductive material, and also how do I supress relay contacts too?
Many thanks in advance

http://www.technobots.co.uk/Technical/Guidance/EMI%20and%20how%20to%20deal%20with%20it.pdfhttp://www.technobots.co.uk/Technica...o%20deal%20wit h%20it.pdf

Try that.

Cheers Ian :)

Ive also noticed that the supply to my electronic equiptment drops a bit when large motors are switched on. Could I use a capacitor across the supply terminals to my electronics to help relieve this problem, and if so what type and how big?

Matt

Whats the problem, a relay not changing over? Generally what people do is put a 4.8volt receiver battery inline so as to up the voltage for the relay. THe will only need to be charged once in a blue moon.

nope, the onboard computer crashes. It works fine up until i use the saw, so Im presuming the problem is due to either a supply voltage drop when running the saw or interference from it. Im planning to suppress all motors, solenoids and relays and fix the supply drop problem (although the supply does go through a regulator anyway) and hopefully that should sort it :)

http://homepages.which.net/~paul.hills/Emc/Emc.htmlhttp://homepages.which.net/~paul.hills/Emc/Emc.html

might be of help

It might be worth a try to put in about 4.8volts extra. It may just solve that problem.

hmm, maybe but i dont want to risk blowing the DC-DC that runs the PC.

Heres an idea, i dont know how practical it is but I am assuming the computer requires little juice. WOuld it be possible to give it its own battery supply?