Inverter overload

[Bluedog225]

What will happen if I run this table saw (13 amps, 120 volts, 1560 watts) with a victron 12 volt, 1200 watt inverter and a 200 amp SOK battery?

The inverters “peak power” is listed at 2200 watts and it has a 200 amp replaceable fuse.

Specifically, will it blow a fuse? Shut down to protect itself? Let out the magic smoke?

I’m thinking little cuts (less than 5 minutes) will be ok. This is in place of starting up the genny.

1. Is that correct?
2. What happens if I run a much bigger load? That is, will the inverter protect itself or will I damage it? I don’t want to kill it as I am testing it’s limits.

Many thanks.

 

[sunshine_eggo]

Surges are generally short enough that fuses don't get blown. Your run current is ~150A, so surge is the only concern.

Running a little above max continuous may be fine for a few minutes, or it may not do it at all. It depends on if conditions are such that the inverter can maintain the voltage and frequency within spec. If it can, it may go awhile. If it can't, it shuts down quickly. The biggest driving factor is inverter temp. It will get hot quickly and throttle its output.

1. That thing may pull near 6000W at startup. I'm not confident it's going to work.
2. This is a much bigger load due to the surge. Generally inverters will protect themselves. They sense the overload and shut down safely.

 

[400bird]

The saw doesn't run at the rated wattage, in easy cuts or free spinning the energy used to spin the blade would be lower.

The biggest issue you're going to see is starting surge. That's an instant hit and will drive the table saw motor at significantly more than the 2200 watt rating of the inverter.

It is probably not going to work because it won't start, not because of the running wattage.

 

[400bird]

Ah, yeah what sunshine_eggo said.

Also, I trust the Victron to be smart enough to protect itself. Plus it's new enough to be covered under warranty if you try it, right?

 

[Bluedog225]

Sounds like it’s worth a shot and (probably) will not damage anything. I didn’t want to break the inverter by doing something dumb, warranty or not.

Thanks all.

 

[Steve_S]

Also watch out because a freewheeling blade (not cutting) is easy but when cutting / loading the draw will go up on the system.
My previous 3000W Pure Sine LF Inverter handled my table saw (120V/15A) but when the saw was loaded cutting maple it was noticeable. With my 4Kw LF Inverter, it doesn't even notice. I do not use HF Inverters because I have some heavy & nasty tools (Mig Welder, Compressors etc) that would kill most HF devices in short order.

 

[HRTKD]

I tried a variety of tools on my 1000 watt MSW Xantrex inverter. The Bosch router worked just fine, probably because it had a soft start (built-in). The standalone air conditioner (12 amps) and the space heater (1500 watts) were both a no go. The inverter simply shutdown. A reset had it up and running again. I would expect no less of the Victron.

 

[timselectric]

It will protect itself.
No harm in trying.

 

[SamDeleted]

@Bluedog225 what about a dimmer , start it low and build it up .

Maybe try run it at 85%~? it'll still cut wood ok at that

This one is not in the states and I think a little small for what you're doing, but you could find something similar

1500W AC Adjustable Speed Controller Variable Motor Fan Control 15A 110V/220V | eBay

Max input power: 1500W. Stepper Motor. Handheld Inkjet Printer. 3D Printer. The back is made of aluminum plate and the buckle is easy to use. Rosin Heat Press Machine. Digital Readout& Linear Scale. This governor is easy to operate, easy to carry.

www.ebay.co.uk

 

[740GLE]

Depends on the motor, if there’s a run cap or starting cap, she won’t like it.

Another option is just pick up a battery powered table. M18 units have plenty of nut if you have enough batteries for the job.

 

[HRTKD]

Another option is just pick up a battery powered table. M18 units have plenty of nut if you have enough batteries for the job.

I've thrown that idea around. I sold my Delta Unifence cabinet saw a few years ago. There have been a few projects that would have benefitted from a table saw instead of a circular saw.

 

[Hedges]

Brush type universal, or induction motor?

Induction motor needs enough volts and amps to start, or it will just sit there drawing 50A and not turning.
An easy-start might help.

Brush-type motor would work with DC or with low voltage AC to start spinning gently.
A dimmer (speed control) could also work. But most are for lower wattage, might have to use gingerly to avoid exceeding control's max current.

You may be able to change the motor.

Or pretend you're starting a model airplane, use an electric drill with rubber nose to give it a twirl.

I've seen 2HP (1500W) VFD for < $80.
Wonder how an induction motor would fare on one of those, bringing out starting winding as 3rd phase? (disconnect VFD and feed straight AC as soon as it is running.)

 

[KITROBASKIN]

Walmart sourced Black and Decker Crisp’nBake toaster oven claims 1150 Watts. Victron Phoenix 24V 1200VA inverter powered by a fully charged Epoch 24V 100Ah battery (Victron charge controller went back to float after test) did NOT maintain load after about 20 seconds. The cook setting was at the lowest; ‘warm’. Bluetooth showed Overload in red after a couple seconds. VA readout showed up to 1290.

We will return the toaster oven. Unless someone has a simple, low-expense method to throttle the power down a little?

Our portable induction cooktop works at the ‘Medium High’ setting (around 900VA if memory serves).
Curious though; a moment after plugging the cooktop in, an internal click sound can be heard and there is a ~50VA standby load. No heating but it is using that much power.

 

[HRTKD]

The 24/1200 is rated for 1,000 watts, so the toaster oven was over that rating.

Maybe this oven will work?




Here's an actual 900 watt toaster oven.

Courant Toastower™ 900W 4-Slice Toaster Oven

Bake, Broil & Toast Functions Only 9 3/4” Wide Stainless Steel Front Large 12 Liter Capacity, Fits 2 Slices Pizza or 4 Slices Bread Choose between Bake, Broil & Toast Functions 30 Minute Timer, Oven signals & automatically shuts off

courantusa.com

 

[KITROBASKIN]

That Easy Bake Oven, is the light bulb included?

Victron is saying our inverter is rated 1200VA continuous, so I thought the resistive load making heat would be ok?

 

[HRTKD]

That Easy Bake Oven, is the light bulb included?

Victron is saying our inverter is rated 1200VA continuous, so I thought the resistive load making heat would be ok?

In your case, maybe try a Black Light.

1200VA = 1000 watts. Your oven was over 1000 watts, ergo, you exceeded the limit. It worked for a bit because the Victron will handle a surge for a short period.

 

[sunshine_eggo]

In your case, maybe try a Black Light.

1200VA = 1000 watts. Your oven was over 1000 watts, ergo, you exceeded the limit. It worked for a bit because the Victron will handle a surge for a short period.

HUH? Victron is no different than anybody else except that they're more honest but less clear about ratings.

Victron inverters are rated in VA. So are all other inverters. Other inverters simply label them Watts. The manuals may give some clue if you dig into them. For the Magnum MS4024PAE, marketing and references always say Watts, but when you dig into the manual, it's VA.

For resistive loads, VA = Watts.
For inductive loads, VA = 0.8Watts

A 1200W toaster oven does not exceed a 1200VA rated inverter. If the inverter gets hot, that 1200VA rating decreases.

 

[HRTKD]

A 1200W toaster oven does not exceed a 1200VA rated inverter. If the inverter gets hot, that 1200VA rating decreases.

His 1150 watt oven pushed the inverter over 1200 VA. He needs a smaller oven or a bigger inverter.

 

[KITROBASKIN]

24 1200 Victron inverter reported toaster oven was taking 1290VA and shut it down after about 20 seconds or so. Black and Decker labels it 1150W. Could there be inefficiencies, and that the heat output is the 1150W rating?

I let it sit then went to a 500W tiny heater and it fired right up. No need to reset anything manually.

Bluedog, Thank you for your forbearance with this tangential talk.