Generator Issues

[TheMan419]

We had a random power outage this AM. As I write this the power outage is on going. Should be resolved in a couple hours per the power company.

In any event becuase I needed to dress up for work today I had to fire up the generator to shower and such. When I ran the microwave to heat some food the generator did not seem to be able to deliver sufficient power. It always has in the past.

Generator is "powered by Honda" but is not a honda. It is 6900 running watts, 8500 peaking watts. Running at the time were two coffee pots, fridge and a couple lights. Should have been more than enough power left for the microwave.

We use the L14-30R plug. We have one of these on the side of the house https://www.lowes.com/pd/Reliance-3...uJgL-1LYSKhIGDvjlTMaAvokEALw_wcB&gclsrc=aw.ds

One change we have made since the last time we used the generator is going from a 40 foot cable to a 100 foot cable so we could put the generator in a more convenient spot. Could that longer cable cause such a power drop?

I'd like to use the multi meter to test the thing. Which holes in the end of the cable would I put the leads of the multi meter into to test how much power I am actually getting at the end of that cable?

Yes I am also googling it, but the experts here are good

Thanks in advance for advice.

TM

 

[workinonit]

Do you have it wired for 240 or 120?

 

[workinonit]

My experience is that coffee pots and microwaves are pretty stout loads. Couple those with the fridge and you could be close considering the voltage drop at 100 feet of cable.

 

[TheMan419]

Do you have it wired for 240 or 120?

Wired for 240 to power the well.

Wire is 10 guage.

EDIT - and as I think about it the coffee pots were OFF. I was using the microwave to reheat the coffee to put in a to go cup to head to work.

 

[Diggin It]

I wouldn't try to run much of any kind of load over 100' of extension cord off a smallish generator.

 

[TractorGuy]

Not enough juice to power a well and two coffee pots IMO.

 

[John_Mc]

What gauge wire did you use for the 100 ft run? I try to keep the voltage drop below 3%. For 100 ft, 12 gauge wire (the gauge commonly used for home wiring) is too small. You really should be using at least 10 gauge wire, and the conductors should be copper (not aluminum).

If you might go to a larger generator some day, consider running heavier gauge wire. (Note that some L14-30 plugs may have a problem accepting heavier gauge wire.)

 

[LittleBill21]

at full load, at 100 feet (don't know internal wiring distance) its only a 5% drop or a 6v drop, you should have been just fine. measure at the outlet where the microwave is, if your above 108V you should be fine.

 

[orezok]

Microwave electronics are notoriously fickle on “dirty” power from small generators. It’s a very common problem with RV’ers.

 

[grsthegreat]

A microwave can suck 1500 watts of power. Was well running at the time. A well can draw a lot of power depending on the depth.

i never would use a 100’ cord on a generator. But that’s just me. I have installed lots of portable back up systems and stick with 10’ cordsets.

but given your situation, I don’t see why the generator was struggling. Did any appliance you didn’t think about cycle, like a water heater or ac unit left on?

 

[ponytug]

I am not an electrician, and this is not electrical advice!

To answer your question, here is an image for L14-30;

https://knoppix.net/store/Cllena-Ne...et-Receptacle-Socket-With-C_184635853241.html

One general point, and a question upfront;

• some microwaves are really intolerant of line frequencies other than 60Hz. I happen to own one, a great little Panasonic, and its' behavior got much better when I did some very minor tweaks to my generator to deliver 60Hz when under the load of the microwave.
• second, how is this generator wired into your house? Transfer switch? Dryer plug?

If it were me, I would check what voltages your generator is putting out unloaded at the generator, then when you have loaded it up close to 6500W. I would also check the frequency. Ideally, you get something like 244V / 61Hz unloaded and 240V / 60Hz loaded. If not, adjust the generator. How close you can get will depend a great deal on the design of your generator. If it were me, I would focus on having the unloaded as close to 240V as possible, while keeping it from dropping much below 238V loaded. I would target 60Hz with about half your load on. (On one of my generators, I ended up on a long excursion of repair before I found a minor issue with the engine that was totally messing up the electrical performance.)

If that passes, I would really want to test two outlets with the microwave running and not running in my opinion. One, the circuit the microwave is on, and second an out let running in the other phase, both hot to neutral, and hot to hot.
Hot to Hot will tell you how close to 240V your generator is delivering at the outlets with no load and under load. Checking hot to neutral on the two 120 phases under load and no load may identify other issues like neutral imbalance issues.

I would always be open to the extension cord having less than ideal connections, and I would be open to any home having neutral or grounding issues, either systematically or at an outlet, or at the transfer switch.

You might find a pair of "Kill-A-Watt" type meters useful for measuring a couple of outlets.

Be careful! These are all high voltage / high power / potentially lethal measurements.

All the best,

Peter

 

[workinonit]

Is the issue with this because the governor on the gen can't maintain proper speed? I don't have this problem with my PTO driven gen.

 

[TheMan419]

What gauge wire did you use for the 100 ft run? I try to keep the voltage drop below 3%. For 100 ft, 12 gauge wire (the gauge commonly used for home wiring) is too small. You really should be using at least 10 gauge wire, and the conductors should be copper (not aluminum).

If you might go to a larger generator some day, consider running heavier gauge wire. (Note that some L14-30 plugs may have a problem accepting heavier gauge wire.)

Using 10 guage and it is copper. If I go larger generator it will be a whole house and properly installed by an electrician.

Microwave electronics are notoriously fickle on “dirty” power from small generators. It’s a very common problem with RV’ers.

This is good to know. Generator is NOT an inverter type. If we do not go whole house standby that will be the next upgrade.

A microwave can suck 1500 watts of power. Was well running at the time. A well can draw a lot of power depending on the depth.

i never would use a 100’ cord on a generator. But that’s just me. I have installed lots of portable back up systems and stick with 10’ cordsets.

but given your situation, I don’t see why the generator was struggling. Did any appliance you didn’t think about cycle, like a water heater or ac unit left on?

Water heater is gas. We specficially unplugged all the window AC units (we do not have central air).

We went the longer cord so that we could put the generator somewhere it is shielded from the elements if it is raining or snowing. We have DETACHED garage. if we put the generator up next to it the weather comes from the other side so it is shielded.

We may need to find another option for that if we do not go to a whole house/standby unit.

Is the issue with this because the governor on the gen can't maintain proper speed? I don't have this problem with my PTO driven gen.

The engine sounded like it was struggling, like I was drawing 6500 watts of power, but there was no way that I was. The well was not runing at the time.

Later when I went to take a shower things seemed to run just fine.

Looks like I will get a kill a watt type device and start to try to track things down.

 

[Gator6x4]

He said he took a shower. Unless he turned his hot water heater off, or it is gas the hot water heater was trying to re-heat the water he used taking his shower.

 

[orezok]

He said he took a shower. Unless he turned his hot water heater off, or it is gas the hot water heater was trying to re-heat the water he used taking his shower.

Yup. Electric water heater can draw 5500 watts.

 

[grsthegreat]

he stated its gas water heater. i would first try a short cord and try to recreate the problem, then go from there.

 

[Diggin It]

He said he took a shower. Unless he turned his hot water heater off, or it is gas the hot water heater was trying to re-heat the water he used taking his shower.

Posted 10 minutes prior and immediately above yours ...

Water heater is gas.

 

[grsthegreat]

this is why i love my 22kw whole house unit.......

 

[TheMan419]

He said he took a shower. Unless he turned his hot water heater off, or it is gas the hot water heater was trying to re-heat the water he used taking his shower.

Water heater is gas.

 

[MossRoad]

...When I ran the microwave to heat some food the generator did not seem to be able to deliver sufficient power. It always has in the past.
...

Was the microwave the only thing running on the generator at that time?