Inverter upgrade

Thread Starter

Haropas

Joined Aug 16, 2019
60
Recently i made a project trying to power a washing machine motor with an inverter of 2000watts and a battery. When I powered the inverter in the motor the motor would turn but when I put a little force on the soft the motor would stop and inverter made a biiib and then stopped. The motor itself it's 350/480 watts. That's why the inverter would turn the motor. But I think when the motor has to deal with some load it will draw more power from the battery and that's why the inverter stops. Is there a way that i can upgrade the inverter to withstand and work properly the motor?

I think the motor when you put load in it needs like 1000 watts to turn so that's why the inverter shuts down the motor

The motor is working properly when you put him on the wall socket
 

Thread Starter

Haropas

Joined Aug 16, 2019
60
Can the battery supply the power? What is it's voltage and current rating? You may just need a better battery.
The battery was a new one fully charged 12 volt 35 ah car battery. i changed the cables from the inverter to the battery to thicker ones and the motor would turn like 5 seconds more and then biiib and the motor stoped. I think thats why is inverter's problem because if i continue i will blow up the inverter .

Is it possible when the motor has some load the watts that it needs increase?
 

Thread Starter

Haropas

Joined Aug 16, 2019
60
The battery was a new one fully charged 12 volt 35 ah car battery. i changed the cables from the inverter to the battery to thicker ones and the motor would turn like 5 seconds more and then biiib and the motor stoped. I think thats why is inverter's problem because if i continue i will blow up the inverter .

Is it possible when the motor has some load the watts that it needs increase?
 

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KeithWalker

Joined Jul 10, 2017
3,063
If the motor draws 2A from the inverter, the inverter will need more than 37A from the battery. What gauge of wire are you using and how long are the wires? If the wire is too thin or too long, you may be dropping too much voltage before the inverter. Make sure the battery connectors are in good shape .The motor will draw more current under load.
 

Thread Starter

Haropas

Joined Aug 16, 2019
60
If the motor draws 2A from the inverter, the inverter will need more than 37A from the battery. What gauge of wire are you using and how long are the wires? If the wire is too thin or too long, you may be dropping too much voltage before the inverter. Make sure the battery connectors are in good shape .The motor will draw more current under load.
I see ... The wire from battery to inverter is as thick as a finger and it says on the wire for high current. But from the inverter to the motor the wire its usual and the same diameter as the motor connector cables . I an test if putting shorter and thicker wire will make a difference. Also i didnt buy car battery connectors. I simply made xontaxt the wires to the battery and put some duct tape around just for testing.
And do you think i need more than 35 ah battery to make this work ? And if i have like a 50 ah battery do you think it will last like 30 minuters ?
 

Tonyr1084

Joined Sep 24, 2015
7,852
1) get a bigger capacity battery.
2) get proper connectors for the battery terminals.

Large wires are good but simply wrapping the wires around the battery terminals is not going to cut it. Battery cable terminals such as this are cheap. And cheaper ones that aren't color coded are available. Go to any automotive parts store and you'll quickly find battery cable ends like them.
 

KeithWalker

Joined Jul 10, 2017
3,063
I agree with Tonyr. It will not work without proper battery terminals. Once you replace them it will probably work OK. A 50AH battery would probably last half an hour if it was fully charged when you started, but you will need a deep discharge one because there will not be much left in it after that. I would recommend at least a 100AH car battery.
 

Tonyr1084

Joined Sep 24, 2015
7,852
I agree with Keith; a car battery is what you want.

Earlier this month we had a wind storm that brought wide spread power outages. Our UPS's couldn't last for the 3 days we were without power. Given that they are old we decided to buy newer units with higher capacity. I now have an extra UPS that I'm going to use in the garage along with one or two car batteries I have shelved. In the event of a brief power failure I should be able to get by for a few hours. Of course, not running large loads, but being able to open the garage door (opener) would be helpful. That and a few lights. If power is out longer than - oh, lets say - three hours I can connect the generator. Proper battery connections and cables will be required. And maybe an alternative battery charger system.

We don't lose power often, but lately we've had a few. Probably as many in the last two years as we have had in the nearly 15 years we've been living here. But the last one was pretty big. The power company had many thousands of outages due to downed trees and power lines. My neighbor lost a big pine tree.
 

Reloadron

Joined Jan 15, 2015
7,501
What does your inverter output as to wave shape? True sine wave, modified sine wave, or maybe square wave? What wave shape does the motor normally run on? You may want to factor in those things on top of everything covered from battery AH rating to supply wire gauge. A 2 KW load @ 12 VDC = 2000/12=167 Amps. That assumes a 100% efficient inverter which does not exist.

Ron
 

Reloadron

Joined Jan 15, 2015
7,501
I agree with Keith; a car battery is what you want.

Earlier this month we had a wind storm that brought wide spread power outages. Our UPS's couldn't last for the 3 days we were without power. Given that they are old we decided to buy newer units with higher capacity. I now have an extra UPS that I'm going to use in the garage along with one or two car batteries I have shelved. In the event of a brief power failure I should be able to get by for a few hours. Of course, not running large loads, but being able to open the garage door (opener) would be helpful. That and a few lights. If power is out longer than - oh, lets say - three hours I can connect the generator.
While you may never see three days without power again you may, in time, wish to consider a generator. Even a small 5 KW unit you could run as needed intermittently during a power outage.

Ron
 

Tonyr1084

Joined Sep 24, 2015
7,852
While you may never see three days without power again you may, in time, wish to consider a generator. Even a small 5 KW unit you could run as needed intermittently during a power outage.

Ron
I can connect the generator.
With the amount of new development and the aging infrastructure, I suspect we're going to be seeing more power failures due to excessive loads. In the past few years there's been a BOOM of new apartment construction in the area. LOTS of new apartments. Main street is clogged all day long every day except Sunday when all the LDS members are in churches. It's getting hard to find a table at local restaurants and the highway has been under construction for the traffic volume expected. Seems like every two years they're adding an additional lane. Too bad they weren't smart enough to build for the future. They only build for the need. Then next year there will be yet more construction. They're already talking about putting a new highway through the bird sanctuary. Good luck with that one.
 

Tonyr1084

Joined Sep 24, 2015
7,852
I15 corridor from Provo to Ogden is as bad as Los Angeles was 15 years ago when I left. Lived in Whittier and worked in Pacoima. 45 minutes to work in the morning, 3 1/2 hours to get home every night. That's a big part of why I left LA.

Now - back on topic: your batteries are going to need to be a lot bigger. Cable is probably OK if you're using something like the battery cables from a car.
 

Thread Starter

Haropas

Joined Aug 16, 2019
60
What does your inverter output as to wave shape? True sine wave, modified sine wave, or maybe square wave? What wave shape does the motor normally run on? You may want to factor in those things on top of everything covered from battery AH rating to supply wire gauge. A 2 KW load @ 12 VDC = 2000/12=167 Amps. That assumes a 100% efficient inverter which does not exist.

Ron
I dont know the wave of my inverter . The sine one is the best i think but if i have an other its waste of time or it can work
 

Reloadron

Joined Jan 15, 2015
7,501
Some motors will run on a MAW (Modified Sine Wave and some not so well. The TSW (True Sine Wave) inverters cost more but also most closely duplicate standard mains voltage. Anyway you have a few things to look over including battery AH capacity and cable size.

Ron
 

MisterBill2

Joined Jan 23, 2018
18,167
I have two small inverters, one is rated at 400 watts out and the other at 800 watts out. Each is about 90% efficient at 100 watts load. The challenge is definitely that power out is at best 90% of power in, and so if you need 480 watts out you need over 500 watts in. 480 watts at 12 volts is 40 amps, and so aside from the battery not being adequate consider that every tenth of an ohm resistance in the battery wires will drop 4 volts. And if the inverter is like both of mine, as the voltage drops the current draw increases.
 

Thread Starter

Haropas

Joined Aug 16, 2019
60
1) get a bigger capacity battery.
2) get proper connectors for the battery terminals.

Large wires are good but simply wrapping the wires around the battery terminals is not going to cut it. Battery cable terminals such as this are cheap. And cheaper ones that aren't color coded are available. Go to any automotive parts store and you'll quickly find battery cable ends like them.
I bought thick battery treminal wires i shorthen also the wires and again a big biib after i put to the motor a load. Also i checked again with a polymeter and I figured out that the inverter gives only 199 volts and not 220-230 and i dont know why
 

MisterBill2

Joined Jan 23, 2018
18,167
Thick wires may not be larger conductors, that is a real possibility. I had a set of heavy-looking jumper cables, each sid as big as my finger. But the conductor was about the size of #10 wire, and it was aluminum. And another set I was asked to fix, again the insulation was fat but the conductor was skinny copper at least Probably good for 30 amps, but not adequate for cranking a car if the car battery is stoned. If you have a meter that can be connected to read the input voltage at the inverter terminals that will tell you what you need to know. Keep in mind that at 1200 watts out a 100% efficient inverter is drawing 100 amps, and 50 amps at 600 watts out.
The funny thing is that my 400 watt inverter came with a cord to plug in the lighter socket and the plug has a 10 amp fuse. That will only just work for a 100 watt load, such as powering a laptop computer.

The wires from the inverter to the motor can be the same skinny size as the ones on the motor, at 230 volts the current will not be even ten amps once the motor is started.
 

Tonyr1084

Joined Sep 24, 2015
7,852
Thick wires may not be larger conductors, that is a real possibility.
I, too, have seen the exact same thing MisterBill is saying. But I noticed you're trying to get 230VAC out. So the numbers would be a little different from Bill's.
I think the motor when you put load in it needs like 1000 watts to turn so that's why the inverter shuts down the motor
On the assumption you want 1000 watts at 230VAC, that equates to 4.3 amps at the 230VAC terminal. To convert 12 volts to 230 (lets assume 240, numbers are easier); 240 VAC, that will require 20 times the battery current. In other words, ~84 amps (at 100% efficiency - which doesn't exist).

Just so you understand, 87 amps - let's give a safety margin - 100 amps the cable is going to have to be a lot bigger than battery cable jumper wires. That's cabling from the battery to the inverter.

Someone check my math. I'm getting a strong feeling the numbers are not correct. Nevertheless, it's going to take a lot of amps to supply the needed current for the inverter to create 1000 watts (VA {volt amps}) @ 240VAC.

Trying to double check my numbers; 1000W ÷ 240V = 4.166••• amps. That's amps for running the washing machine motor. 12 volts at 1000 watts (again, assuming 100%) would require 83.33••• amps. Big battery and big cables.
 
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