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:
Soundguy:
You are correct. I do have two adjustment pots above the display. I was not sure what their function was so I did not touch. Do you happen to know if the display board is just for display or if it plays a roll in cutting the power should it go above 132 V? D currently have mine pulled and I am reading the same voltage before the EMS and after the EMS.
Obviously I'm not privy to an authorized schematic of these EMS units but from what I can tell the readout display is just that - reads out the voltage inputted to the EMS circuit board. Adjusting the trim pot(s) adjusts the input voltage down (or up) but the low voltage cutoff threshold of 104 vac is fixed. In other words, if you adjust the voltage down using the trim pot(s) the voltage display will drop accordingly and when it hits just a hair below 104 vac the unit will disconnect. I've not tested the high voltage cutoff as I'd need a Variac (which I don't own) as a voltage source but I'd assume it's functionality would be the same. I wouldn't touch these trim pots though without having a calibrated meter on hand since there's no point in making any adjustments unless they're accurate. My EMS was originally reading about 1.4 volts high compared to the actual voltage being inputted to the unit, now it tracks very closely with my calibrated DVM and as luck would have it with my Kill-a-Watt meter. :B
