I want to run my Graves Mark IV off my inverter in my campervan, so I can look at pretty scenery while I facet. I can’t find any info on what kind of amperage it draws. Probably all faceting machine motors are similar. Any motorhome or off-grid faceters here that can give an idea? I’ve got 1000 watt hour Goal Zero solar powerbank and it would be great not to have to be connected to shore power at a campsite.
All electric motors have a sticker on the machines… Anything that plugs into the wall is a 110/120v
and should have the amps on the sticker. the sticker should be either on the sides or back of the machine or Under it. It has to have it. after doing some digging i found someone selling one that has the lable on it and they say its 1.2 amps at 115 v. That would mean its 138 watts. which makes sense since they only run at like 600 rpm.This is where i got the info. https://www.worthpoint.com/worthopedia/used-graves-mark-iv-faceting-machine-455977420
Most faceting machines that are variable speed are D.C. to begin with, since you cannot vary the speed on an A.C. motor.
You might want to look into having your Mark IV modified to run solely on D.C., it currently has a rectifier circuit to change thee voltage from 115 Volts AC. to Volts DC.
I am not sure what the exact voltage requirements are for most faceting machines is, but it should not be much over 8 -10 volts or possibly less, and the current draw would be quite low, since there is not much friction during the cutting process.
Well that’s a take I hadn’t considered but of course it makes perfect sense, thank you.
Which would be 11.5 amps at 12 volts, kind of high for my purposes but do-able on a sunny day (solar panels). I may consider Rockrat’s suggestion to convert it to run straight DC.
Just look at the plate data on the motor. By law they all have to tell what they draw. Some will be in watts, others in amps. The average wall outlet in a house will service 15 amps; or 1800 watts. Chances are the motorhome will be the same.
Your 1000 watt hour powerbank is what will likely be the biggest limiting factor. That power designation means (assuming a full charge) that it will provide 1000 wats for one hour, 500 watts for two hours or 250 watts for 4 hours and so forth. Hope it helps.
Thank you Dennis. Solar panels charge the battery during the day, it’s a matter of whether they can keep up with the draw. I like to go into the night with at least 20% left. Could be this is an activity for campsites with electric. Or maybe I need to spend several thousand dollars on more batteries for the luxury
Also keep in mind that the startup current draw on an induction motor is roughly four times the amperage needed to run the thing. The drain will last a few seconds while the rotor spins up to speed; but your inverter will have to have the appropriate surge capability to cover it.
Many of the modern machines run variable speed DC motors, 12 or 24v and usually around 0.15kw, so current draw will be around 12A (12v) or 6A for 24v unless you ‘lock-up’ in which case current rises significantly, limited by the speed controller which is usually rated at 40A
The inverter is 2000 watts, it’s just the battery capacity, and the load compared to what my solar panels can compensate for, that I am concerned with.
To work out the amperage there is a simple calculation:
Watts divided by Voltage equals Amps. Hopefully from that you can see how it will impact on your inverter. I don’t know the Graves machine but assuming the motor is 100w like the lamp it is just under an amp on 110v. Using the lamp as well would add another amp.
Hope this is of some use