Phase Loss Monitor having false triggering ( bad capacitors issues)

[sam_sam_sam]

These phase loss monitor modules have two boards one board is basically the power supply board the other board is basically the phase loss monitor circuit

It has three capacitors on it one on the power supply board 470uf@50volts (KMG) 0.11 ESR value
The other two capacitor are on the phase loss monitor circuit board

One capacitor is 10uf@63volts (Unknown brand) replacement capacitor automotive grade low ESR
One capacitor is 100@50volts ( unknown brand) replacement capacitor was 100uf63volts automotive grade low ESR

The results of the ESR are as follows 0.70 this was a very low value for this capacitor compared to a new one
The other value was 1.7 this value was very close to a new one but I do not remember which value went to which capacitor I am sorry about this

Will test this phase loss monitor tomorrow at work and see if it works correctly or not

Here is the website link where I buy these modules

https://www.grainger.com/product/ICM...chQuery=icm408

One interesting thing that is in the data sheet it says that it can operate at a temperature of 149*F really one of the capacitor was only rated at 85* this is why I went with automotive grade capacitors except one of them I did not have the power supply board capacitor in that grade on hand

[redwire]

Re: Phase Loss Monitor having false triggering ( bad capacitors issues)

It would nice to see pictures of the inside of the module. It must use a small mains power transformer?
I repaired a simpler phase loss detector and I think it was damaged from spikes 480VAC monitor circuit, cmos IC got zapped. Yours has so many trimpots.

[stj]

Re: Phase Loss Monitor having false triggering ( bad capacitors issues)

philips and rubycon make some 135' caps for use in stuff like boiler ignition boxes that get cooked.

[redwire]

Re: Phase Loss Monitor having false triggering ( bad capacitors issues)

Nichicon also has some new solid polymer capacitors to 125°C/257°F or 135°C/275°F or 150°C/300°F. But that is where plastics melt and most wire is only rated well below that. The league of teflon wire/pcb and special semiconductors.

At high temps and many years, I find electrolytic capacitors usually dry out, but the Philips blue ones short. So C value goes down and ESR goes up.

Lifetime is halved operating every 10°C above 40°C/104°F, according to Nichicon.

[sam_sam_sam]

Re: Phase Loss Monitor having false triggering ( bad capacitors issues)

Well the phase loss monitor was reinstated and worked very well for 8 hours today