power meter wiring question

[tacomabill]

Total electrical noobie here. I have an AGM battery in my camper that will run a compressor fridge that has only a DC power supply with a cigaratte lighter dc plug. I would like to get a power meter like the Wattsup to measure how many amps are consumed over 1-2 full days. If I keep the fridge I will add solar, solar controller and a smart battery monitor, but for now just want a cheap way to measure amps.

So, hooking it up to battery is obvious, but how to connect the Wattsup to the fridge? The meter has bare wires with no connectors so I have no idea how to connect it, and I do not want to install the Wattsup in a permanent way. If there is a more portable meter, or simpler way, that measures amps over time, please advise.

 

[1Louder]

You just need to build something. I used SAE plugs. One side with alligator clips to go to a battery. You could use terminal ends if you wish. Then another SAE connector to the fridge side. So Alligator to SAE and then SAE to 12 Volt female. Sorry that I don't have a better picture. My setup allows me to test whatever I want and is portable.

 

[john61ct]

SAE is fine for light loads.

If you might be measuring large currents (lower than your meter's rating of course) go with Anderson connectors.

Very handy having the ability to measure accurately at various strategic points around your system, both charge sources and loads.

When you have an opportunity, check for accuracy, calibrate against e.g. a known-good Fluke clamp ammeter.

Cheaper ones can be pretty good, and don't need to be inline.

 

[dwh]

You could take one of these, cut it in half and stick the meter in the middle. Just MAKE SURE you get the +/- right.

 

[tacomabill]

Looks like my best solution is a cigaratte lighter adapter like this one which is about $6 USD. I think all I need to do is take the red and black wires and connect them to the same colored wires on the load end of the Wattsup meter. Then plug my fridge cigaratte lighter plug into it. then attach the power source wires to the battery as shown in the diagram from the Wattsup website. Sound right to you guys?

 

[john61ct]

I just hate ciggie ports, fundamentally unstable design prone to intermittent, arcing even at low amps have melted surrounding plastic.

But for temporary use under 6A I s'pose...

 

[1Louder]

I just hate ciggie ports, fundamentally unstable design prone to intermittent, arcing even at low amps have melted surrounding plastic.

But for temporary use under 6A I s'pose...

I agree. They are one of the worst connectors. So you might want to consider using SAE or Anderson in your vehicle setup. I used and ARB Wiring kit for convenience but have an SAE power port instead of the 12 volt cigarette style plug that came with the ARB. Place like Amazon or Powerwerx.com will have everything you need.

 

[dwh]

for now just want a cheap way to measure amps.

...

I do not want to install the Wattsup in a permanent way.

Did you guys even bother to read the OP before replying?

 

[john61ct]

Sure, putting in Anderson connectors at various strategic points in your setup is a great way to benchmark volts and amps using meters like a Watts Up temporarily.

And they offer much greater information over time than a clamp or Hall effect ammeter, if that's what you're suggesting.

Only cost $30-40.

I assume great accuracy requiring a calibrated Fluke costing hundred$ is not in the OP's requirements.

 

[dwh]

No, I'm suggesting the guy just wants a quick and easy read on how much his fridge draws.

So why the hell would he need to futz around with SAE or Anderson connectors?