Many RV'ers keep a multimeter handy for those electrical tasks at hand. With all of the meters available on the marketplace, how do you know which is a good meter to throw into your RV's tool box? A multimeter is defined by a meter that can measure many different things.

Typically, voltage, current (amperes), and resistance (ohms) are the basic functions. Additionally, Frequency (Hz), Battery Test, and Temperature (with a remote probe) are nice-to-have features found on some meters.

Even an old vintage multimeter such as the PSM-6, as shown to the right would do the job in most cases (a bit of nostalga here - if you were in the military in the '60s~'70s, you would have used one of these).

There is nothing magical about a meter for RV use, but there are a couple of features that may come in handy. I would choose a meter with the minimum:

• Voltage measurement.
• Ohm measurement.
• Audible Ohm scale (continuity).

You may notice I did not include a Current (Ampere) function. Fact is, most multimeters having a current function is not sufficient for RV use, so it is not a priority.

There is a valid reason to measure current - such as for parasitic loads or leakage current (which typically drains your battery), however a generic multimeter is not the best tool for measuring it.

A Clamp Multimeter is the tool to use for these currents, and it would be a good choice for a second meter... perhaps not in your RV's tool box, but maybe in your home workshop.

In addition to the basic necessities, useful features include either a combo Analog/Digital meter, or a Digital meter with a bar-graph that approximates the analog movement. This is useful for varying voltages.

Two of the best brand name meters are Fluke and Keysight. There are a couple of others in that league, but if you want the best, go with those. Keysight is interesting. Prior to the 1990s. Hewlett-Packard was well known in the electronics industry for having some of the finest electronic test equipment. When I was an electronics/communications technician in the 1970s, HP was one of the most respected brands of test gear.

But when HP began building computers and printers, they spun their test equipment division off and became known as Agilent. And history repeated itself in the second decade of the millenium, when the test gear operation split again. Agilent became the lab equipment group, and the test equipment group became known as Keysight. So... today's Keysight test gear heritage is Hewlett-Packard. Kind of a strange name though.

It is often not necessary to purchase a commercial grade multimeter for your RV, especially if you are going to be banging it around out in the woods. Often, an inexpensive ($25) meter will be sufficient. I call these "toolbox" meters... those that give you adequate accuracy, and are cheap enough that if they break or are stolen, you won't be out a lot of money.

My personal preference for a toolbox meter is a combo analog/digital multimeter, which gives me the best of both worlds. They are not as common these days, but they can still be found. And an audio annunciator on the x1 Ohm scale is essential in my view - especially for a digital meter - as it allows you to rapidly test continunity without having to wait for the digital display to stabilize.

The meters on my recommended list are:

• Keysight U1242B - perhaps a bit overkill to throw in your RV toolbox, but a very good professonal meter.
• Fluke 115 - if you want a professional grade digital multimeter.
• Tekpower TP7244L - if you want an inexpensive but nice analog multimeter.
• Tekpower TP7310 - technically a digital meter, but provides both Analog and Digital displays.
• Mastech MS8211 - if you prefer a "Pen" style multimeter.
• Mastech MS2108A - 400A AC/DC Clamp meter
• B&K; Precision 316 Mini AC/DC Clamp Meter

One difference between an analog and digital voltmeter is it's impedance. Digital meters will not "upset" sensitive electronic circuits like an analog meter can, however in a RV, there may not be occasion to need that capability often. So I would say for a RV, you will be mostly measuring primary DC (battery voltages), so unless you know you will be working on electronic circuity - buy the one you prefer, as they will both work fine. But if you are doing electronic work - buy the digital meter.