Reliance Controls 30-Amp Indoor Wattage Meter

Adding the Reliance (inductive) wattage meter in line with my new generator input feed to my main panel gives me visibility to load balance for optimal generator efficiency for my whole panel generator backup.

The meter was easy to install, was immediately confirmed to work with first generator test, and it looks to be well built and and a bargain.

After replacing my small 35 year old circuit panel with a new Siemens 4040 panel, I wanted to change from using a generator subpanel with only 10 circuits to a whole panel generator backup.

The one great thing about the generator subpanel was that it had wattage load meters so that I could insure circuits were arranged for reasonable load balance between the two legs for optimal generator efficiency.

I selected an interlock bracket kit that enables me to dedicate the first two slots on the top right breaker column as a generator back-drive breaker. The interlock bracket bolted to the face of the panel physically insures the main breaker and generator breaker are always in opposite positions to satisfy codes.

This is an easy way to supply generator power to the whole panel, but with simply adding a circuit to a plug-in for the generator, there is no way to check load balance between the two legs so that one or two circuits could be swapped across legs if needed (something you hopefully only need to do once or twice to get reasonable balance).

No local big box store or electrical supply in my area had load meters that I could find. Luckily, a web search led me to the Reliance meter box. I'm a "do it myself" home improvement guy, and this dual meter box was super easy to splice into the wiring between the panel and generator wall plug.

A quick test while on the generator with an 1800 watt hair dryer on various settings performed on each leg quickly verified meter function.

If it works for the long term just as it did after installation, I'm a very happy guy.

Adding the Reliance (inductive) wattage meter in line with my new generator input feed to my main panel gives me visibility to load balance for optimal generator efficiency for my whole panel generator backup.

The meter was easy to install, was immediately confirmed to work with first generator test, and it looks to be well built and and a bargain.

After replacing my small 35 year old circuit panel with a new Siemens 4040 panel, I wanted to change from using a generator subpanel with... more

I recently installed a Briggs & Straton 8KW generator for emergency back-up during power outages. I also installed the Reliance 30 amp watt meter MB75 to monitor the watt load. I was pleased with with the meter except for the very short pick-up leads( only about 12 inches long) much too short to reach my generator leads. I had to splice an additional 12 inches into all 4 leads. The meter was not cheap. I don't understand why the leads were so short. I also installed the Reliance PowerBack alert. The unit works as it should except it's not loud enough. 86 db is not very loud unless your house in very quiet, which mine is not most of the time.

I recently installed a Briggs & Straton 8KW generator for emergency back-up during power outages. I also installed the Reliance 30 amp watt meter MB75 to monitor the watt load. I was pleased with with the meter except for the very short pick-up leads( only about 12 inches long) much too short to reach my generator leads. I had to splice an additional 12 inches into all 4 leads. The meter was not cheap. I don't understand why the leads were so short. I also installed the Reliance PowerBack... more

The Reliance MB75 is perfect for generators with total outputs up to about 7500 watts. In this model, each meter reads 3750 full scale, with each meter displaying current flow through each leg of a 240 Volt line. The meters are not of exceptional quality, but will probably serve their purpose if not dropped or mis-handled.

The meter is designed with two toriod current transformers on short leads connected to the meter terminals which use push on terminals. In most installations, you would have to route 10 AWG Romex back and forth to the watt meter to enable each leg of the 240 Volt line to go through each toroid current transformer.

If you can mount this watt meter right next to your generator cable box, you can then use the short leads provided to directly connect the toriods to your generator leads. This is a much easier installation than running heavy wire back and forth to the meter. Also, it is possible to splice additional wire into the toroid leads to extend this length if you can't get the watt meter close enough to the generator leads. This is also easier than running heavy wires to the watt meter.

Although I believe this is a worthwhile product, it is really not a watt meter since it doesn't also measure the voltage and just assumes that it will be 120 Volts AC. It measures current and displays that information on a volt meter calibrated in Watts. It specifically warns you that the meter is designed for 120 Volts and will not give accurate wattage information if the voltage is something else.

All in all, a good and inexpensive solution which is really needed when using a generator.

The Reliance MB75 is perfect for generators with total outputs up to about 7500 watts. In this model, each meter reads 3750 full scale, with each meter displaying current flow through each leg of a 240 Volt line. The meters are not of exceptional quality, but will probably serve their purpose if not dropped or mis-handled.

The meter is designed with two toriod current transformers on short leads connected to the meter terminals which use push on terminals. In most installations, you would... more

The meter uses nearly the entire depth of the box, so it's nearly impossible to wire it from top to bottom.

It works fine to wire it through the bottom and side knockouts.

I finally had a chance to test the watt meter. It performed as expected, very good. I was able to balance each leg of my generator feeds. And I knew exactly how much load was on my generator. I think this is a very good and useful tool to have.

My generator is an older model Honda an EM3500 that I have had for 9 or 10 years and it still performs like new. I purchased the MB75 meter to see how well I have been able to balance my electrical load over the years with such a small wattage generator 3500 watts and I was surprised that I had balanced my load to around 1000 to 1200 watts on each leg with normal running not appliance start-up. My generator is connected via manual transfer switch into the breaker box and I can run anything in my 3 story house as long as I stay under the 3500 watts. This year I will be upgrading to an 7200 watt generator.

This MB75 meter is a great addition to my setup even though they could have made the leads a little longer to make the installation easier.

My generator is an older model Honda an EM3500 that I have had for 9 or 10 years and it still performs like new. I purchased the MB75 meter to see how well I have been able to balance my electrical load over the years with such a small wattage generator 3500 watts and I was surprised that I had balanced my load to around 1000 to 1200 watts on each leg with normal running not appliance start-up. My generator is connected via manual transfer switch into the breaker box and I can run anything in... more

I recently installed a Briggs & Straton 8KW generator for emergency back-up during power outages. I also installed the Reliance 30 amp watt meter MB75 to monitor the watt load. I was pleased with with the meter except for the very short pick-up leads( only about 12 inches long) much too short to reach my generator leads. I had to splice an additional 12 inches into all 4 leads. The meter was not cheap. I don't understand why the leads were so short. I also installed the Reliance PowerBack alert. The unit works as it should except it's not loud enough. 86 db is not very loud unless your house in very quiet, which mine is not most of the time.

I recently installed a Briggs & Straton 8KW generator for emergency back-up during power outages. I also installed the Reliance 30 amp watt meter MB75 to monitor the watt load. I was pleased with with the meter except for the very short pick-up leads( only about 12 inches long) much too short to reach my generator leads. I had to splice an additional 12 inches into all 4 leads. The meter was not cheap. I don't understand why the leads were so short. I also installed the Reliance PowerBack... more

Wanted to have a meter to show power load on both hot legs in my electric panel. This fit the need exactly to the generator I was using- 4000 watts or 30 amps. This is an extremely high quality product. I was able to switch some breakers around in my panel so I could balance the load better.

I checked its results with my Amprobe and they were accurate. I ran 10 wire into the watt meter box and ran one hot leg through the hoop provided and the other hot leg through the other hoop as you would using an ampmeter. The results were exactly what I wanted. I like the analog meter because it shows high draw as blowers stat or compressors start and then as draw falls after start up. Excellent product all around.

Wanted to have a meter to show power load on both hot legs in my electric panel. This fit the need exactly to the generator I was using- 4000 watts or 30 amps. This is an extremely high quality product. I was able to switch some breakers around in my panel so I could balance the load better.

I checked its results with my Amprobe and they were accurate. I ran 10 wire into the watt meter box and ran one hot leg through the hoop provided and the other hot leg through the other hoop as you... more

I installed this between the feed from the generator inlet and the breaker panel. I use a Generator Interlock Kit to prevent the possibility of back feeding the utility. Even though I only have a 5500w generator I wired everything to handle up to a 12kw generator. This meant #6 wire all the way through and a 50amp power inlet. I used an offset nipple between the meter box and the breaker panel and some Liquidtite flexible conduit out to the power inlet box. Made for a neat, clean and professional installation. I also mounted a standard battery powered emergency light at the panel to help me see what I'm doing while I'm getting the generator setup during an outage. All i need to do if I upgrade the generator is replace the two small edge meters with the ones from the larger one. Much easier than ripping it all out and starting over. Ordered the meter and power inlet from EGD. Meter was shown as backordered when I ordered it but i was not in a rush. Everything came when expected.

I installed this between the feed from the generator inlet and the breaker panel. I use a Generator Interlock Kit to prevent the possibility of back feeding the utility. Even though I only have a 5500w generator I wired everything to handle up to a 12kw generator. This meant #6 wire all the way through and a 50amp power inlet. I used an offset nipple between the meter box and the breaker panel and some Liquidtite flexible conduit out to the power inlet box. Made for a neat, clean and... more

I installed this yesterday very close to the panel board. The leads are too short and need to be 6-12 inches longer or more. If you don't have space right next to your panel board and generator breaker, the leads may be too short and would have to be lengthened.

It would be nice if the five leads (2 from each meter and the ground) could have a sleeve to neaten the job. I installed one myself out of #10 Ga 3-1 NM. I have not tried it yet, and hope it works next time the infrastructure crashes.

I installed this yesterday very close to the panel board. The leads are too short and need to be 6-12 inches longer or more. If you don't have space right next to your panel board and generator breaker, the leads may be too short and would have to be lengthened.

It would be nice if the five leads (2 from each meter and the ground) could have a sleeve to neaten the job. I installed one myself out of #10 Ga 3-1 NM. I have not tried it yet, and hope it works next time the infrastructure... more

This is a great meter to monitor and balance generator output.