Campground power stand tester

[weaselguys]

I was looking at a few web sites discussing power stand testing and saw this picture the first one of one pieced together to test the voltage and polarity of a 30 amp stand, so I decided to make up my version and I bought a short and long 30 amp plug just in case the short one was to hard to see.

 

[Alaskansnowbirds]

That will work for 30amp but will only check one leg of 50amp.

 

[weaselguys]

It is for 30 amp only, I don't need 50 amp.

 

[SargeW]

Nice work, can you come up with one for the 50 amp guys?

 

[Lou Schneider]

Testing a 50 amp outlet is more complicated because you also have to a) verify that there's 240 volts across the two hot legs and b) put a load on one side of the circuit to verify the neutral is intact and can carry current.

The simplest 50 amp tester I can come up with is two duplex outlets in a quad box, one pair of outlets on each leg of a 50 amp pigtail.  Plug in one of those 3 light + voltmeter testers on each leg, leaving an open outlet on each duplex.

Test the integrity of the neutral by plugging in a fairly high draw device like a hair dryer or an electric heater into one of the open outlets and observe the voltages while it loads one side of the 50 amp pair.  If the voltages stay the same, the neutral is OK.  If they widely diverge, you have a bad neutral.

The only other addition would be a way to verify there's 240 volts from one hot leg to the other, to verify the 50 amp outlet is actually being fed from a 240 volt source.  I don't know how to do this using plug-in components, but you could install a 240 volt pilot lamp into the electrical box.  Light on = 240 Volts leg to leg, which is what you want.  No light = 0 volts leg to leg, not good.

 

[John From Detroit]

Home made 50 amp site tester
You need
1 50 amp male pigtale (plug with cord tinned leads or stripped leads)
one double size outlet box. extra deep is nice
Optional a couple of push to reset circuit breakers 15 or 20 amp depending on next item
Two duplex outlets  15 amp or 15/20 amp (I'd go with 15/20)

Hook up as follows
Black to (Optionally a circuit breaker to) one copper colored screw on one outlet (or both of 'em)
Red.. same path other outlet
White.. To both SLIVER color screws
Green to either ground if a metal box. both grounds if plastic.

Additional need
one or two Three Light Testers
one or two volt meters

Plug 'me in and see what you find.

Optional  50 amp FEMALE cord.. Splice to male cord now you have an in-line break out tester.

 

[Gary RV_Wizard]

Here are plans for a 50A outlet tester.  Simple and inexpensive components and easy enough to assemble..

http://www.myrv.us/electric/Pg/tester_50amp.htm

However, if you buy a better quality surge protector/monitor, it will have polarity checking built in as well as high/low voltage & frequency tests.

 

[SargeW]

Nice Gary! Simple, easy to use, and not too pricey.  Right in my wheelhouse!

 

[grashley]

As Gary said, get a Progressive EMS, hard wired or portable, and it will test everything.  Not only that, it will continue to test AND PROTECT the RV from high and low voltage as long as it is plugged in, not just when you check.  It will shut down power when a problem is detected.

 

[SargeW]

Actually I have one, and have had in the last 6 RV's I have owned. However, many people will read this thread and may not want, or be able to afford one. I knew that by asking the brain trust here on the forum that there would be many other options offered. It's more important to have the ability to check for poor or improperly wired electrical pedestal than to not do it because you can't afford to buy the high dollar model.

 

[HueyPilotVN]

The Progressive EMS will also tell you several other things.

It will show you if you are on shore power or generator power.

It will show what amount of power you are hooked up to, 50 amps, 30 amps, or 20 amps.

If you are on the generator it will show you how many amps you are pulling.

If the EMS is shedding circuits due to low power it will tell you which ones are still live by the green lights.

The third panel in the picture is for the Xantrax Invertor.

It shows the current charge type. Bulk, Accept, or Float.

The first column is the current voltage of the batteries.

The second column is the amount being used, and the green light indicates that the Invertor is on.

The third or right column shows the amount of A/C input power, in this case greater than 30 amps, (actually 50 amps).

 

[weaselguys]

I agree with everyone about the about the Progressive EMS it will tell you a lot more, but for me right now I boondock 95% of the time so a EMS is a lot of money to spend for that 5% and I was simply thinking of a cheap way to tell if the site power is ok before backing in. One day I will get a EMS but not for now.

 

[grashley]

Actually I have one, and have had in the last 6 RV's I have owned. However, many people will read this thread and may not want, or be able to afford one. I knew that by asking the brain trust here on the forum that there would be many other options offered. It's more important to have the ability to check for poor or improperly wired electrical pedestal than to not do it because you can't afford to buy the high dollar model.

Marty,  I agree with you.  This thread had focused almost exclusively on the affordable option.  I wanted to mention the better, but clearly more pricy option, too.

 

[SargeW]

And I whole heartedly agree with you Gordon!

 

[cavie]

I was looking at a few web sites discussing power stand testing and saw this picture the first one of one pieced together to test the voltage and polarity of a 30 amp stand, so I decided to make up my version and I bought a short and long 30 amp plug just in case the short one was to hard to see.

FYI. The "Power Stand" is called the Pedistal the RV world.

 

[ELeland]

I like Gary's version of the home made unit.  I haven't sprung for the Progressive unit yet due to cost.