Voltage variations and Surge cut off.
We are hooked up to 50A service. I just recorded the voltages at different areas and I will note them below. I have a Progressive EMS/Surge suppressor hard wired in just before the breaker box. It has...
Forum Discussion
joelc wrote:
This leads me to think that the LED display on the EMS is giving false voltages.
I read your original post several times and didn't quite understand your concern until you posted the above which indicates you're questioning the accuracy of your EMS's monitor panel readout, not it's ability to accurately connect or disconnect to power. Since you originally referred to your unit as being "hardwired" into your rig I'll therefore assume what you have is a Progressive Industries EMS-HW50C, essentially the same as my own EMS-HW30C. If so, open the EMS and you'll likely find a couple of trim pots similar to the single trim pot I have in my 30 amp version ...
Yours being a 50 amp may have 2 of these trim pots. This trim pot adjusts the voltage readout on the monitor panel but does not affect low voltage or high voltage cutoff thresholds. I trimmed my own against a known calibrated DVM but it's a bit of a guess since the EMS's readout only reads to full volts, not tenths. That said, I did manage to get mine to track quite closely to my calibrated DVM. All this said, it's hard to believe your EMS could be reading as far off as you claim - a volt or two I can see but anything more than that I'd wonder why.
A series of 10 pics of my own EMS-HW30C starts here.
