Multimeter for the Boat

[kungfoo]

Originally Posted by thomm225

Also things like Oscar had a hairy old ass.

Or

Old hippopotamus Alice had zero apples

Sine, Cosine , Tangent.

Sine =O/H

Cosine = A/H

Tangent = O/A

Let's not forget:

On Old Olympus' Towering Top A Fin And German Viewed Some Hopps

sorry, got a bit lost there for a moment.


Restating one of my initial observations regarding multimeters, as the conversation seems to have wandered somewhat, any modern DMM with reasonable measurement confidence (that you would trust when you're stranded in the middle of the Pacific) will likely have all the bells and whistles you'll need (such as capacitance measurement). I don't think I've seen any contradictory evidence in this thread thus far, and it appears to stand firm.

Glancing through again, I don't see much that might contradict the opinion that measurement confidence is important, or that a $10 cheapo which starts giving false readings as the battery dies is unlikely to have it.

I've never encountered a single situation in which I *needed* a DC clamp meter. That being said, in retrospect, I can think of several situations in which it would have been very nice to have.

Does anyone have any model-number recommendations for a DC clamp meter?

Does anyone have any good examples of things you really just can't do without one?

[Bruce K]

When I buy a new meter, the two most important things to me are
1. Can I hear the continuity buzzer? (I have high frequency deafness)
2. Will it turn itself off when I forget to? (Battery not flat next time I use it)

[noelex 77]

Clamp meters are invaluable on a boat. If you only want one meter, buy a clamp meter. Most models come with probes in addition to the clamp function, so they will also function as a conventional multimeter to measure voltage etc.

If you are keen on electronics it it still worthwhile in addition buying a high quality conventional multimeter, as these have more functions and a more accurate voltage display, but for most owners a clamp meter on its own will do everything they want. This can be supplemented with one of the very cheap conventional multimeters if you want a back up.

Originally Posted by kungfoo

Does anyone have any model-number recommendations for a DC clamp meter?

Make sure the clamp can measure DC amps. Some of the cheaper models will only do AC, which is near useless on a boat. I use a Fluke which is overkill for most users, but before this I used a cheap no name clamp meter. The cheap meter was fine, other than it failed with no warning just when it was most needed and I when it was impossible to organise a replacement. This was after a decade of use so it was not poor value for money, but the failure was inconvenient.

Originally Posted by kungfoo

Does anyone have any good examples of things you really just can't do without one?

The ability to measure current without cutting the wire or gaining access to the ends is invaluable and this can only be done with a clamp on meter.

A simple example where you cannot do without one is tracing wiring on a boat. If you are not sure which particular wire in a bundle behind a cupboard supplies say the water pump, turn on the pump, turn everything else off and the clamp meter will show which wire is carrying current.

There, now you have an excuse to buy one .

[team karst]

I use this one.

Not super unique, but it is my goto marine meter.

Sorry Thomm, not the best for TWT grid current. [emoji848]

[kungfoo]

Originally Posted by noelex 77

A simple example where you cannot do without one is tracing wiring on a boat. If you are not sure which particular wire in a bundle behind a cupboard supplies say the water pump, turn on the pump, turn everything else off and the clamp meter will show which wire is carrying current.

There, now you have an excuse to buy one .

lol...you know me well

::drools::

[BobMc]

We bought this one based on recommendations from various sources (no longer remember the sites) and it worked well for us. Don't forego a clamp-on meter - you'll soon wonder why you never had one sooner!

https://www.amazon.com/UNI-T-Digital...011680011&th=1

[abarrow]

I'm a retired electrical engineer and do work for myself and others. I got one of these a few months ago: https://www.pokitinnovations.com/pokit-pro/

While I wouldn't recommend it for your only DMM, it's REALLY nice to have a simple oscilloscope as well as a data logger, DMM, etc. in a light, rechargeable package. It's easy to use, and being able to put my phone (as a display) nearby not wired to the test probes is a benefit I didn't expect I'd appreciate as much as I do. It's now my go-to meter and gets carried with my tools, whereas my other DMMs are increasingly left at home.

Even if you don't get one of these, having a one-piece style of DMM with the probe and display on one end like a fat pencil, and the other test lead coming from it is hugely convenient as opposed to having a meter with two leads coming out laying in come inconvenient place that's constantly getting pulled off.

While I fully understand the issues of accuracy with low-cost DMMs, in my experience the number situations where super high accuracy actually matters is comparatively low.

Your mileage (or voltage, resistance, whatever) may vary!

[bullislandken]

Originally Posted by thomm225

I didn't get myself a used Fluke.

I would never pay that much for a multimeter.

I was just letting others know that you can get a good used quality Fluke 87 III for $174 on EBay.

I wouldn't mind having an old analog Simpson 260 though. It was what we used in the 70's every morning because we had to readjust all the power supplies that had drifted.

We also troubleshot with them.

These days though you very rarely ever have to check power supply voltages. They simply don't drift

I have two old analog Simpson’s I have used for the past 45 years. Tenths of volts can be hard to distinguish on some scales in low light, too. I bought an Anchor with the DC clamp on amp meter primarily for that feature and I really do like having that feature. Seems like I paid about 120 bucks for the Anchor in year 2000. Even with the reliable Simpson’s, the Anchor is still my best one (even tho the leads suck and it only goes to tenths of volts). I must have a few other DMM’s and the Milwaukee one is nice but only AC camp on ammeter.

[daydreamer]

When you turn it on to measure voltage, does it default to AC or DC?

I had to swap my home meter and boat meters -- I rarely measure DC at home and rarely measure AC on the boat.

[thomm225]

Originally Posted by bullislandken

I have two old analog Simpson’s I have used for the past 45 years. Tenths of volts can be hard to distinguish on some scales in low light, too. I bought an Anchor with the DC clamp on amp meter primarily for that feature and I really do like having that feature. Seems like I paid about 120 bucks for the Anchor in year 2000. Even with the reliable Simpson’s, the Anchor is still my best one (even tho the leads suck and it only goes to tenths of volts). I must have a few other DMM’s and the Milwaukee one is nice but only AC camp on ammeter.

Actually I haven't used a Simpson in years.

We have an old Simpson 260 here at work though, but it has no battery and is quite dusty.

We have four Fluke 87 III's and a few other no-descript multimeters maybe a Precision and a Milwaukee but I don't get those calibrated. Plus we just don't use them much any more.

Most of these systems tell you what is bad with the flashing lights etc and with I/O we use Phoenix so it tells you also.

https://www.phoenixcontact.com/en-us...te-i-o-systems

The computers numbering in the 100's on separate networks a meter isn't needed to troubleshoot those either.

These new computer/cell phone tech courses we have to get qualified with don't even mention meters or O'scopes.

Times have changed. I don't think my young tech age 28-33 have ever used an O'Scope. They are mostly Cyber/Computer techs.

When I ask them what if the UPS (ours have 32-72 12 volt batteries plus a bypass select depending on which simulator we are talking about) fails and you have no power. They say put it in Bypass and get one of the old guys to check it.

The young techs have to spend all their time learning computer, software, and cyber so the schools just touch on basic electronics for techs.

For tenth's of volts on the boat, I used that old $15-$20 meter I've had now for a few years plus now I have my Victron display for Battery and solar info.

Last time I did much troubleshooting here at work it was on some old late 1990's 20" CRT Monitors and since we had good schematics and could power them up I usually used one of out Trektronix O'Scopes.

[bullislandken]

I am not near my multimeters since my daughter had an early c-section so I flew to Boise. Baby and mom doing well.

I believe my Anchor DMM has a switch for AC or DC clamp on ammeter. I recall if I forget to switch, it gives weird readings that make me check the switch. I also recall I need to zero the MM when using the ammeter and the dial is a bit “course” so it can be hard to get to settle at 0.0 before clamping around ONE CONDUCTOR, but it still gives useful readings even if not zeroed. To me, I like having access to a clamp on meter on all my boats or rigs that have a battery. I have not searched to see if my meter is still available.
Ken

I have loaned it to other cruisers that ask for one on the cruisers nets. Mostly it is returned with a new 9 volt battery, too. I love this community. At 66, I am not ready to give it up but my wife is.☹️

[steveberl]

I've had an Extech MA445 True RMS 400A AC/DC Clamp Meter
(https://www.amazon.com/gp/product/B01IB4N3YG) for a few years now and think it is great. It's done everything I've ever needed onboard.
Haven't tried dunking it in the water yet.

[FlyingScot]

I'm partial to Fluke but there are other good choices.

Fluke 101 - basic, small, light, don't even keep it in a case. Just in a pocket in one of my electric tool bags. It's also the one I loan or take to help others.

Fluke 365 for clamp on ammeter use. It's easy to use but 200A max capacity is limiting these days.

Fluke 87V. This stays in a nice case. It was NIST certified once. This is used more to check the other meters. At one time I checked multiple meters of mine and some cheap $15-20 ones from Amazon. Most were within a 0.03 of the 87V when working with voltages between 11-14v. My 25 year old Fluke 76 was within 0.01v.

If you are a do it yourselfer you need a decent DMM.

[Sailing Hanse37]

Agh, as an electronics engineer my experience is: buy the cheapest multimeter you can get. You hardly never ever need precision measurement on a boat. BUT i have a good reputable brand clamp on DC Amp meter

[thomm225]

I've used this old cheap meter for years now on the boat.

Works great.

No clamp on amp meter so far but maybe one day.

Had the boat for 11 years without needing one.