I travel full time with a 38 foot fifth wheel trailer. Sometimes my options for electrical hookups are very limited. It gets pretty tricky figuring out what equipment we can run when we are only plugged in to a 15 or 20 amp outlet. Does anyone have any ideas either where I can find or how I can build some kind of amperage meter that will allow me to constantly monitor the amount of amps I am using?

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dhadik

 

Cheapest way is to just buy a 0 to 30 amp, amp-meter.

I got some at a reasonable price $8.00 plus Postage.

Gary

 

DC amps or AC amps?

I have a cool AC ammeter I picked up from a traveling tool sale... it was like $2 or $3 ... it clips around the hot lead in an ac circuit and tells you the amps, no need to break the circuit

it's a bit overkill for measuring anything less than 2 amps but it works good in the circuit panel checking for which breakers are close to capacity

I think the range on it is 20, 200, 2000 .... don't know that I'd want to be stickin my hand anywhere near a line carrying 2000 amps

 

Touching a 2000A conductor is quite ok, provided it is ELV (extra low voltage) - less than about 50V, and that it is of adequate cross-section, otherwise it will heat up and burn your hand :roll:. Don't, however, put your credit cards near it, or they might get erased :P I have previously found myself sitting inside a 4000A switchboard at full load (but only about 12V), I'm still in one piece...

The idea of a clip-on ammeter is probably the easiest, but remember that you must clip it around ONE wire only (either hot/active or neutral) but not both. If you clip it around both, the currents in the active and neutral cancel eachother out, and the meter will read zero.

 

In order to be useful it would seem that the meter/readout would need to be inside the vehicle so you could adjust what you are doing knowing the reading. The place to make the measurement, without significant rewiring, is likely in a spot that's not easily accessed. This suggests to me, a two-part package consisting of a sensor and meter. The sensor might simply be a current transformer paired with a matching meter that can be remotely located. I'd look in Square D and similar electrical manufacturer's sites. Some RV dealers may carry just what you want - your problem is likely to be very common. Where my RV is we suffer from low voltage and I am told it's quite the common problem at RV parks.

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stevez

 

Radio Shack has been selling this AC outlet meter called "Kill-A-Watt'. It is very cool, you can read amps, volts, power, or kwh used. They've been putting it on "clearance", but sometimes they seem to just do that to keep it selling. It was around $25. I dig it, I wondered how much power it took to leave my PC on all day (264 watts with the monitor, 167 without).