How to make a 240V 50 amp Digital Voltage Monitor (DIY) Project

[@itninja9503]

shouldn't you be goin to the Neutral, not the ground for the meters power?

[@FDRGREG]

Great Job! I have this on my breaker box inside but it is fixed not movable. I would like this and being able to move around. I bet you could sell these as a finished product for ?$. These look like same exact meters I bought and installed. Nice engineering!

[@tonyw2641]

Really nice work, Gavin. Can you provide the links for the box? Also, what tool did you use to make the cut-outs in the faceplate? Thanks.

[@Ophrahoak2]

Great Job. You are on my Subscribed list. I'm adding this to my generator hook up

[@BestKaylee]

Thank you so much for the great video. You always have the best information presented in a clear, concise way. Keep up the great work, my only suggestion would be to have someone hold the camera or use a tripod a little more often.

[@GeneratorReviews]

Yeah, sorry about that. I switched to the tripod and 4K camera now learning curve.😅

[@chip2139]

I noticed the whiskers sticking out on the terminals. Stranded wire is always twisted clockwise. Hint: Twist the exposed stranded wire counter-clockwise. Then the screw tightens down on the wire, the strands will be drawn in. Problem solved. Power is calculated by multiplying the voltage times the current. The reason for the voltage connection. The things you are calling monitors are called Current Transformers or CT's

[@GeneratorReviews]

Thanks buddy 👍🏾 great tips

[@SlwRpr]

Hey good job young man. I just purchased a gas powered generator, i like your idea and i will have to attempt to make one for mine. I will have to re-watch your video for the instructions.

[@bluecerulean]

Why do you need two monitors ? Trying to set up something to monitor watts from generator to home . Thanks

[@GeneratorReviews]

Since the generator has 240 V, you need two monitor, one for each leg easier to keep your generator load balanced.

[@mikecr4916]

He is measuring 2 phases of 120v loads, and messed up for a 240v load. The thing about a 240v load, let's say it's 10amp, that single 10amp portion is seen on both legs. So with measuring both legs and summing for total, you would be doubling that single 10amp. That's wrong, so you would have to do some testing and write down somewhere the 240v compensation for this (Gen Supply calibration). If your loads are purely 120v on both legs, you can use 2 meters for balancing potential, or you could use just 1 meter. To use 1 meter, run both hot legs through a single CT, with one hot leg passed through the CT in the opposite direction (looped). That would give you accurate total 120v loading. The same problem about a 240v load exists here(doubling).

[@linuxsurfer2002]

@@mikecr4916 But isn't it true that the 10amp portion of one leg is only 120V, so if you are measuring watts, you do need to measure both sides and add them together?

[@rodneygouthier6090]

Nice job Gavin. Just what I was looking for. Thanks again 👍.

[@dontronge9874]

Very cool. I wonder if I could attach the meter to my 50amp breaker wires and mount the box next to panel to monitor gen usage when using gen and not utility power. That DIY kit would be a big seller man!

[@GeneratorReviews]

You could make that happen thanks for watching 👍🏾

[@willag1]

Are those UL approved hose clamps?😆 You may want to find some cable gland connectors.

[@GeneratorReviews]

Last minute decision😅

[@Tom-In-Ga]

Nice, neat, simple, and it works. Nice job!

[@Carperama]

If this was not power from a gen but power from the grid how would you figure the total wattage from say a well pump using two hot wires? Would you add both meter readings together for overall wattage since I'm trying to figure out what wattage my well pump is? Thanks.

[@GeneratorReviews]

Yes that is correct ✅

[@Carperama]

@@GeneratorReviews I only have one monitor now so I guess I can temporarily put it on each hot wire just to figure wattage.

[@tommartin5217]

How did you strip the insulation off the middle of the cable without nicking the insulation? I am using a piece of 10/4 soow cable.

[@GeneratorReviews]

Just use a very sharp razor blade and be extremely careful

[@cliffthomas1389]

Quick question. Do the wires powering the meter need to be attached to the same wires that you are measuring? I'm installing on my generator and it would be easier to get power to the monitor by using a different source .

[@GeneratorReviews]

The power of the meter uses you can’t even measure so it should be OK you’re not gonna get a different reading just powered before the meter.

[@Bob-mm9sm]

I made a unit like this and it did not work on my conventional generator. It worked fine on the Inverter Predator 9500 I have. With the old Powermate generator the display just flickered a little. I'm assuming the power isn't clean/stable enough for device to work. It might with a power conditioner but I won't be getting one to test that. I just thought I'd mention this.

[@jamesalles139]

yeah, power for the monitor should be taken from a hot and Neutral (white); never Green.

[@cartrip2559]

Great video. I am just subscribed. I have the generator connected to my main electrical house panel via gen inlet and 50 amp breaker. Can I use the 2 monitor clamps on that 50 amp breaker wires? I could then connect the monitor ground to the panel ground bus. Where would I connect monitor power? I plan to have the 2 monitor displays in the house, so should I power the monitors using a regular wall outlet? Thanks for your response.

[@GeneratorReviews]

Yes you can power the monitor from a separate outlet it would work 👍🏾

[@cartrip2559]

@@GeneratorReviews So I can have the 2 clamps on the 2 wires on the 50 amp breaker inside my panel and then have the 2 monitors inside my house. I can probably cut and modify a regular extension cord with hot, neutral, ground, and connect the monitors to a regular wall outlet. Anything that you can think of that I am forgetting? Can the monitors handle 110v coming to it?

[@pb4610]

Current should never be on the ground. The meter should be connected to white (neutral).

[@lawrencepikas7519]

What gauge wire did you run from the #6 solid wires in the 6 x 6 x 4 box to the monitor?

[@GeneratorReviews]

It’s 6 gauge wire I just stripped back the insulation in the middle

[@garden-queen2393]

Nice job. You made it look so easy 👍.

[@gabrielflores741]

So to find overall power usage (kWh) would you just add the to number together?

[@GeneratorReviews]

Yes that is correct 👍🏾

[@growingpains9623]

Would it be safe to use a 50 amp range/dryer cord to bring down the price and cut back on some of the work?

[@GeneratorReviews]

That could work as long as it’s a six gauge wire

[@bullrdr1982]

I built a 30a version of this using l14-30r plugs. The displays seem to work, but I am not getting a reading on the watts. The other units display fine (ie amps, frequency, and kWh). Do I have something hooked up wrong?

[@GeneratorReviews]

Check your wiring connection

[@mrrickcrushing]

Hi, Gavin, great instructions, I built this last night but I am going to use it for a more or less permanent mount beside my main panel so I can watch my gen when it is under load. I intend to put the conductors around each leg in the internal portion of the inlet box from outside, my question is: I need to add about two feet to the black/red wires from each conductor...using the same gauge wire, do you think that will induce delta into the accuracy of the readings or will that still be ok? I am thinking ok but never hurts to ask, lol. Thanks!

[@GeneratorReviews]

You should be perfectly fine! 2 feet not gonna change anything That’s pretty awesome you made one. Thanks 👍🏾💯

[@richardedwin5980]

Can I use this same set-up with the predator 9500 even though it doesn’t have a 50amp outlet? I have the 30amp to 50amp splitter cord already. And run a 50amp cord from there to my inlet box.

[@GeneratorReviews]

Yes, you can use the same set up. Just have the 30 amp plugs.

[@richardedwin5980]

@@GeneratorReviews I have the 30amp to 50amp splitter cord and connect that to the 50amp cord that runs to my inlet box. Would I still use the 30amp plugs or the 50amp?

[@jasonhouston7249]

Just came across this and thinking about it for my Predator 9000, I have a 240v/ 30 amp twist lock, curious if I can use one meter with the clamp around both legs and it will add up the total wattage? Or is it necessary to wire up 2 meters, one for each leg. I'm thinking I'd like it plugged directly into generator, mounted to frame (if it doesnt vibrate loose), then run my cord to inlet at the house. Thoughts?

[@GeneratorReviews]

I would have to test this out, but I think if you put one on the neutral wire, it will read both legs

[@JALBANESE5]

Nope, you can't use one meter (current transformer, CT) as you describe if you want an accurate reading of total wattage. To accurately measure the total current (or watts) drawn from the generator, you would need to place one CT around each of L1 (arbitrarily, the red conductor) and L2 (arbitrarily, the black conductor), otherwise, because L1 and L2 are 180 degrees out of phase, the opposing currents will partially/fully cancel each other out if measured together, resulting in an inaccurate reading of the total power being drawn.

[@jorgeesteban3709]

Hi Gavin, great video. Can you post a link for the box. It looks like a 6" X 6" X 4".

[@GeneratorReviews]

You can pick that box up at Home Depot

[@condor5635]

Nice but for me mounting this project box all near my electrical panel made more sense. That way it is always close at hand to view and is 'permanent' to the house and out from the elements. It only lights up/turns on when I switch the interlock over to generator power.

[@TheHelimechanic]

what gauge wire are you using for the power monitor wires?

[@GeneratorReviews]

I used 8 gauge wire for this project

[@props-model-shop]

Real nice. Must make one myself.

[@chrisyerp174]

Built many of these boxes in line or on the side of braker pannels but iv never seen hose clamps for lockers lol. NEC turn your head lol

[@GeneratorReviews]

lol 😆

[@darrenglynn597]

I would like to know what (wattage ) my industrial fan heater is drawing as it can draw up to (16 amp ) using a (13 amp) plug I do not want to make it draw to many amps to do another melt down on the plug. Like what happend on Sunday 25 December at 09:45hts. I was unaware that the thermostat was on it maximum power. Hence the burn out.

[@gl3882]

Hi Gavin, Thanks for the great video, I was wondering if you've seen a WiFi version of these meters and if so, would they be just as accurate?

[@GeneratorReviews]

Yes they are just as accurate

[@robertkinnan3478]

Do you think this could be adapted safely to measure my main panel instead of a generator?

[@GeneratorReviews]

They have one that works great for what you need

[@robertkinnan3478]

@@GeneratorReviews I purchased the ones you show on this video. Do you have a link to what you think would work?

[@christurner5473]

That meter is bad ass, when you start selling your shirts you totally got start selling these meters to. If you were gonna start selling those how much would you sell them for. Could you use those on any generator??

[@GeneratorReviews]

Hey Chris Definitely I will be making those I’ll sell them as a kit DIY kit Haven’t thought of a price yet, but it wouldn’t be that much

[@rockcralwer]

Man you should sell theses I'd buy one

[@waterboy74]

Shouldn’t you have connected the meter power to the neutral instead of ground ? Aren’t you using ground as a return for the meter power the way you did it?

[@GeneratorReviews]

You have to connect it to the ground because connected to the neutral is for your 240 V reading

[@angeloguzman1426]

Hello Gavin, thanks for the video. I built one this weekend. It looks like it’s working, but I have a question. I connected to a Predator 9500 using a 25’ 10AWG cable. Interlock, etc. No AC or other heavy loads. The top meter read 123 Volts, 6.591 amps and 563 watts. I’m not an electrician, but OHM’s law tells me the watts should be 810 not 563. The bottom meter had similar readings. Also, the top meter had PF reading of .61 and the bottom meter read .50 PF. That should ideally read close to 1.00 and .90, or thereabouts. Does the PF affect wattage output? To any electrician out there, what does a low PF in this case mean? Are my wires loose? Any help or observations would be greatly appreciated. Thanks

[@GeneratorReviews]

Just make sure you orientated your clamps the right direction

[@angeloguzman1426]

These clamps don’t have an arrow to indicate orientation.

[@angeloguzman1426]

Hey, even though I did see any arrows which would point to a proper orientation, I did have mine in placed in opposite directions. Once I changed one of them and both were oriented toward the same direction, problem solved. Thanks, much appreciated. The PF reading is now 1.0. @@GeneratorReviews

[@aperales5455jazz]

White to neutral. not white to ground or green. Green is for the grounding.

[@JavierRivera]

Hey. Is that an adapter cable that came already with the connectors or is a soow 6/4 cable and you added the connectors. If it is a adapter that came all in one can you provide the link?

[@GeneratorReviews]

Hey Javier What’s up buddy All the pieces came separately. I’m going to add all the links.

[@JavierRivera]

@@GeneratorReviews thank you. The Hurricane Ian came by my house. I lost power and I was able to power my whole house with the GM9000iED. Stove is gas, dryer gas, 2 AC units- 3ton and 2ton. With both ac running, refrigerator and anything else that is normally connected like internet etc I was running the generator at 4,800 watts. 💪🏼

[@GeneratorReviews]

@@JavierRivera nice 👍🏾

[@sh839c]

@@JavierRivera So does the GM 9000iED put out 240 volt for the ac units?.

[@JavierRivera]

@@sh839c that is correct. 240v and 50amp. I have a few videos on my channel

[@GAMINGKID12147]

will this tell me a rolling use for a total of lets use an example of 30 days? I am trying to see how much power a 5th wheel is using so I can charge them for total KWH. thank you

[@GeneratorReviews]

Yes it has a meter that counts total kWh used and it is resettable

[@holdenbreau7187]

What is your background are you electronics or electrical tech? Also did you ever look into a 100 amp device?

[@darrenglynn597]

What meters have the clamp (iron cores) can I get them from Amazon.

[@GeneratorReviews]

Check out the link in the description

[@valentincampos8436]

Could you use only one monitor with thinner wire?

[@GeneratorReviews]

Yes you can for 120v kzbin.info/www/bejne/gneViGyGpNCji7M

[@valentincampos8436]

@@GeneratorReviews thank you sir

[@gone4days956]

Gavin would this be the same for a L14-30R 4 prong?

[@GeneratorReviews]

Yes it would be the same

[@tluva1020]

Just found your vid. Nice work!! Question... I'm currently making something similar & would like your thoughts. 3 meters in a box, on a diy parallel Y cable, that will connect 2 120v generators to a 120v 30a RV outlet. A meter measuring the output of each gen, & the 3rd meter measuring the combined output of the two gens. The idea is if I mix 2 different gens, like a 2,000w & a 3,500w, or a 1,600w & 2,200w, I could see if they are sharing the same load equally or if the bigger gen is carrying more load as it should. I'm wondering if the meter readings will be affected incorrectly by back feeding each other since essentially they're all on the same circuit leg. What do you think?Thx!

[@GeneratorReviews]

That should work fine I don’t see any issues with your idea 💡 good luck 👍🏾

[@tluva1020]

​@@GeneratorReviews thx 4 the reply. I'll give it a shot!

[@mikebutters4540]

Ok, I did what you showed unfortunately one of my legs always seems to flash when it's plugged in to 240v do you have any suggestions I'm even plugged it into a 240 wall socket can I get one leg that flashes I'd appreciate any comeback from anybody thank you

[@GeneratorReviews]

You must’ve missed something because mine doesn’t do that.

[@prezzzrock]

Would this work for a 11,500 running watts, 14,500 peak watts generator?

[@GeneratorReviews]

Yes

[@mikebutters4540]

I'm sorry but I'm done exactly what you've done and my monitors don't seem to pick up any current and when I have the monitors in place like you do I'm only getting a quarter of the bolts out but it's a funny thing to monitors are sometimes working and sometimes not working and this is the second set of monitors I've tried. What am I doing wrong. Sorry smartphone at put the word bolt but I said volt.

[@GeneratorReviews]

They are direction sensitive you have to make sure the monitors are facing the same way

[@earthenergyhex]

cool, thx for the video, subscribed

[@GeneratorReviews]

Thanks for watching and subscribing👍🏾😎

[@richardedwin5980]

Is the junction box metal or pvc?

[@GeneratorReviews]

It’s PVC

[@mikemurray8423]

Just saw the A1volt 10000 watt invertor, what do you think? Review...

[@GeneratorReviews]

I just wish it had a 50 amp plug for a 10000 watts generator

[@mikemurray8423]

@@GeneratorReviews that's what I thought, love your videos

[@ceebee4334]

Can you use 10/4 SOOW cable for this?

[@rjen34772]

10 gauge wire would only be good for up to 30 amps

[@ceebee4334]

Agreed. My setup is all 30 amps from the generator to the house generator inlet so I can duplicate this setup Gavin has outlined but with 10/4 SOOW I am assuming. I just want to be able to monitor the 2 legs off of my 240 30amp outlet…..and want to do it safely.

[@twsconsulting]

Why green instead of white. I think power should be taken from line to neutral, not ground to line......It is true that neutral and ground are bonded in some installations, but not all....

[@GeneratorReviews]

If you take it from the neutral wire your monitor will never show zero because it always measures the power from the monitor. RVs, transfer switches and most generators are bonded

[@brandongolder4492]

Does this calculate kilowatt hours?

[@GeneratorReviews]

Yes it does

[@browsedeweb8834]

Shouldn't the power to the meters be the hot and neutral? Neutral is current carrying where ground is not, and for accurate power readings, you want to measure voltage across the load. See the 5th diagram down in the Amazon link you posted up top.

[@GeneratorReviews]

Most generators are bonded, the ground and neutral wire coming from the same place and you have to get your power reading from your hot wire I guess that’s why I showed a test. It works great and it goes back to zero with no load.

[@browsedeweb8834]

@@GeneratorReviews My Honda is floating neutral. Probably no big deal, but as an engineer I'd still follow the wiring diagram since that is the recommended method.

[@busterhyman6633]

@@GeneratorReviews So if you unbond the generator to backfeed an inlet would you do hot and neutral?

[@bluecerulean]

Also, I have a RVGUARD 4 Prong 30 Amp 50 Foot Generator Extension Cord from Amazon that I connect to my generator and home do I follow same setup? Thanks In advance. Can I just pay you to make one? Lol😅

[@GeneratorReviews]

I can make you one that’s not a problem

[@bluecerulean]

Not sure how to get you my contact info I think it keeps getting deleted from here

[@bluecerulean]

@@GeneratorReviews figured out how to get your email from the desktop just send you my info. Thank you sir !

[@tluva1020]

Use proper strain relief

[@GeneratorReviews]

Yes, I just ordered the correct wire clamps This was done last minute. I plan on doing an updated video.

[@RobertJohnVenable]

Awesome, might do this myself

[@FirstSuiGeneris]

Nice!

[@GeneratorReviews]

Thanks 🙏🏾

[@J.R.F.23]

So I priced it all out and in most cases you would be looking at $70-$100 depending on parts stock (for those that don’t gave any of the parts. I.E.: Work box, pair of monitors, 10/4 wire. Male & Female ends and weatherproof connectors. YES being able to monitor usage would be nice (since many generators don’t have it built in). But us in necessary, due to the fact that most generators usually have overload/over draw protection built in… 🤔