Progressive Industries Ammeter not reliable?

[Mark N.]

I have the EMS-PT50C and it's currently plugged into a 30A outlet while my trailer is parked behind my house. I checked and it was reading 0 amps with nothing on. Good enough. I turned my newly installed Fan-Tastic fan to high and walked out to recheck the EMS. 1 amp showing, though the FanTastic Fan should be hitting nearly 3 amps while on high! Huh??
I went in and turned on 13 of my lights (All LED) along with the Fan-Tastic Fan on high still, went out to look and it had only raised to 2 amps! Huh??
Turned off the fan, left the 13 lights on, and again, 1 Amp showing.
I KNOW the fan and 13 lights are drawing more than 2 amps! Am I missing something?

[K0LCB]

Your EMS is measuring AC current, your lights and fan use DC from your battery

[Mark N.]

quote:Originally posted by K0LCB

Your EMS is measuring AC current, your lights and fan use DC from your battery

My understanding an amp is an amp, regardless of it being AC or DC? Therefore the measurement shown on the EMS would be the current draw on the converter as a result of the fan running. I actually know very little about electricity, and usually just enough to get myself into trouble.

[jcurtis934]

The converter may not be reacting to what is being pulled out of the battery at that time. When I have been looking at my readout when an ac load came online, such as an air conditioner, firplace, etc...it was real close to what reality would be. Plug in a 120vac device into the outside socket and turn it on while watching the readout. Our converters aren't smart enough to react to very small dc loads put on a battery that can supply high amperage for hours before decaying in charge levels. Hope that helps assure you all is well. John

[Bigboomer]

Mark,

The read out you are getting is from the converter kicking on to charge your house batteries as the lights and fan draw from them. The EMS is reading AC current drawn thru from the pedestal.

As for AC amps and DC amps there is a difference and here is how the two are get to difference:

AC amps x Vac (volts of your AC device) = Watts

Example: 1.6 amps x 120 Vac = 192 watts

To find DC amps from Watts use the formula below.

Watts/Vdc (volts of your DC system) = DC amps

Example: 192 watts / 12 Vdc = 16 DC amps

Hope this helps.

[Mark N.]

Thanks all! That makes sense to me now.