Power Inverters

[Ken98660]

Hello everyone,

I'm a newbie Tormek owner who happens to be living in the USA where the standard power configuration is 110-120 volts. My problem is that I'm trying to size a power inverter so that I can run my brand new Tormek machine "off grid" from the back of a big old van. I already have a 400 watt and a 500 watt power inverter. The Tormek machine is rated for 200 watts. The question is, do you think my existing equipment is sufficient or will I need to upgrade to a larger power inverter ?

[Dutchman]

A search for "inverter" resulted in  several topics e.g.: https://forum.tormek.com/index.php?topic=3198.msg18565#msg18565

[cbwx34]

Just make sure you search from the Home page of the forum (or it won't search the entire forum).

You might also contact Tormek support... see if they have any info.

[BeSharp]

Hello everyone,

I'm a newbie Tormek owner who happens to be living in the USA where the standard power configuration is 110-120 volts. My problem is that I'm trying to size a power inverter so that I can run my brand new Tormek machine "off grid" from the back of a big old van. I already have a 400 watt and a 500 watt power inverter. The Tormek machine is rated for 200 watts. The question is, do you think my existing equipment is sufficient or will I need to upgrade to a larger power inverter ?

The only way to find out is to try it. That's because it depends on the inverter quality. I would derate a cheap inverter by 200-300% (i.e., use a 400 - 600 Watt rated inverter to run 200 Watts). If it's a better quality inverter (Statpower, etc.) then no derating might be needed.

Second, Tormeks (no electronics) are probably fine with a square wave inverter; electronics are sensitive to non-sine wave inverters. However, having a sine wave inverter is better, and would also lower current draw. Check with Tormek.

Third, the starting (inrush) current can be several times higher than the continous 200 Watt rating. That depends on the motor. In short, the only way to see if it works is to try it. See if it starts, and see if it gets uncomfortably hot after running it for a while.

I built a self-contained power supply (https://forum.tormek.com/index.php?topic=4784.msg34260#msg34260) a while back, and used it this past Sunday sharpening garden tools at a local nursery. The battery/inverter unit is the one below the Felco logo, with the two cooling fans.

[bisonbladesharpening]

Hello and best wishes
I run a mobile set-up out of the back of my truck.
Use an AGM marine battery and a 2000 watt modified sound wave. 
powers my T8, Nikon low speed 10" paper wheel set-up, Viel 1x40, twice as sharp scissor set-up
Sometimes need more start-up amps for the nikon.  3 years and all still working well.  RIP Wootz.

[Ken98660]

My warmest thanks to everybody who responded to this thread, you've all been extremely helpful.

[Ken98660]

Hello and best wishes
I run a mobile set-up out of the back of my truck.
Use an AGM marine battery and a 2000 watt modified sound wave. 
powers my T8, Nikon low speed 10" paper wheel set-up, Viel 1x40, twice as sharp scissor set-up
Sometimes need more start-up amps for the nikon.  3 years and all still working well.  RIP Wootz.

Let's say that I only want to run my Tormek model T-8 and nothing else. Do you think I'm going to need such a big power inverter ?

[John S]

Finding what size power supply is pretty easy if you purchase a KILL-A-WATT power meter.  I believe you can detect peak (inrush) current as well as average use.  Then it is simple multiplication to figure out how large of a battery you will need. 

If the T8 draws 200 watts and you want to run it constantly for four hours that is 800 watt hours.

John

[Ken98660]

I spoke to a representative at Don Rowe.com and was told that it would be real easy to determine the correct size power inverter. All I need is the "locked rotor amperage" rating of the Tormek  T-8 machine.

You'd think that somebody at Tormek would be able to provide this key piece of information.