Multi-Meter Recommendation?

[Mischief Managed]

I am something of a tool junkie.I am going to have to check this out. Another tool I have is a "Power Probe 4". It is more for automotive and has a 60V max capacity, but still has many cool features and uses. $120.

That's funny, I have a Power Probe too. They are brilliant for troubleshooting 12V circuits and a total game changer.



Another awesome tool you may want to buy if you don't have one already is this set of 30 foot test leads: https://www.harborfreight.com/30-ft-retractable-test-leads-58024.html

 

[Waywego]

Another Power Probe user here. With long enough leads, it is fantastic, both for troubleshooting and also as a temporary power source during installs. I bought it for use with vehicles and trailers, but have used it just as much on the boat.

 

[grahamdouglass]

$2 voltage tester vs expensive Fluke

I may have told this story on here before but here it goes.
I went to start my Northern Lights genset one day and it wouldn't start.
Out comes my Fluke meter and I start to measure voltages starting at battery connection. It shows 13.8 volts . I go down the line into the genset control box, 12 volts here and 12 volts there. I phone the guy at Northern lights. It just won't start and it measures 12 volts.
I then take my cheap $2 voltage tester, the one that has a light in the handle and looks like screwdriver with a sharp end with an alligator clip on a wire at the other end. NO voltage, at the control panel, no voltage at the 12Volt connection in the lazertte, but voltage at the battery where the large cables between the battery and the genset connect. Problem was a fault in the 20 foot connecting cable battery to genset.
The multi-meter was measuring WITHOUT LOAD. The cheap tester had a load, which was the little light. This often comes up when you have a bad connection with your windless.

When there is no load enough voltage will get through to give a reading. As soon as a load is applied resistance will overpower the connectivity. At least this is my understanding.

 

[marcs]

When there is no load enough voltage will get through to give a reading. As soon as a load is applied resistance will overpower the connectivity. At least this is my understanding.

Correct. It can also be helpful to use a meter in min/max mode for this sort of thing to see how low the voltage drops when you put load on it (eg. try to start it). Most of the meters I've seen mentioned here have that feature.
The advantage of having the voltage as a number is you can then work backwards along the circuit back to the battery to quantify where the drop is and thus where to focus further.

 

[Eli27]

Fluke 123. Why? Why not. Add an Amp clamp and no need for anything else.

I've been in electrical since a child taking apart remote controls and stuff. Served me well in the auto industry. I was a traveling diagnostics and accumulated tools.

So I got lucky having the 123 as an extra tool.

For those who don't know the 123 is a 2channel scope. I have a few different scopes and the 123 was just an extra for the extra just in case the extra needed an extra.

 

[Mischief Managed]

I may have told this story on here before but here it goes.
I went to start my Northern Lights genset one day and it wouldn't start.
Out comes my Fluke meter and I start to measure voltages starting at battery connection. It shows 13.8 volts . I go down the line into the genset control box, 12 volts here and 12 volts there. I phone the guy at Northern lights. It just won't start and it measures 12 volts.
I then take my cheap $2 voltage tester, the one that has a light in the handle and looks like screwdriver with a sharp end with an alligator clip on a wire at the other end. NO voltage, at the control panel, no voltage at the 12Volt connection in the lazertte, but voltage at the battery where the large cables between the battery and the genset connect. Problem was a fault in the 20 foot connecting cable battery to genset.
The multi-meter was measuring WITHOUT LOAD. The cheap tester had a load, which was the little light. This often comes up when you have a bad connection with your windless.

When there is no load enough voltage will get through to give a reading. As soon as a load is applied resistance will overpower the connectivity. At least this is my understanding.

In my experience, this is a super common problem in marine DC circuits and it typically stumps folks that don't troubleshoot marine electrical stuff often. My marina offers no repair services and there aren't many mobile marine electrical guys around here, so people in my marina often rely on DIY troubleshooting out of necessity. When they get stumped, they often come to me for help and this issue is one of the first things I check for. In small current circuits, it's usually a corroded spade terminal or corroded fuse.



I have developed a strong hatred of spade terminals and uncovered fuse blocks on boats...

 

[DDW]

When there is no load enough voltage will get through to give a reading. As soon as a load is applied resistance will overpower the connectivity. At least this is my understanding.

In fact, a figure of merit for a DVM is how little load the meter puts on the circuit (the input impedance). That is why you should always test with the circuit under load - real load, not a small light bulb, especially in high current circuits.

Fluke 123. Why? Why not. Add an Amp clamp and no need for anything else.

Problem with that is, a Fluke DC clamp that will measure down to ma. costs around $500 minimum, way more than one with the clamp built in.

 

[TowLou]

Flule all day long. My all day meter is a Fluke 117 it goes in 480/277v cabinets every day. I would love a fluke 87 if the price is right but need to get a better amp clamp first. Looking for a deal to pop up again on the Fluke 378FC. Need a bigger amp clamp.

 

[ronobrien]

Correct. It can also be helpful to use a meter in min/max mode for this sort of thing to see how low the voltage drops when you put load on it (eg. try to start it). Most of the meters I've seen mentioned here have that feature.
The advantage of having the voltage as a number is you can then work backwards along the circuit back to the battery to quantify where the drop is and thus where to focus further.

In automotive/truck/equipment service industry we call that "voltage drop test". We always felt that it was the ONLY way to test resistance in a circuit and to verify circuit integrity.