200 watt sunforce inverter alarm

[blacksox]

Hi,
I have two 100 Watt Renogy panels and one group 27 deep cycle battery. I have a 20 amp MPPT charge controller. Per my kill-a-watt meter, my AC devices are using 9 - 11 watts, 123 - 124 volts and about .14 amps. I have romex running about 30 yards from the shed with the solar panels to a chicken coop where the AC devices are (two foscam cameras, digital daylight timer for the coop door motor and two led lights with one being on a motion sensor). I'm trying to troubleshoot my 200 watt inverter because the alarm is going off as soon as I plug in the devices. However, if I plug a lamp directly into the inverter, it works fine. I have not tried the lamp plugged in for too long, just a minute or two. When I use my sunforce 1000 watt inverter, it seems to be working fine and the AC devices are working. It is my understanding that I should be using a smaller watt inverter, like the 200, to be more efficient. Also for troubleshooting, I'm able to plug the AC devices into an AC extension cord and it does not flip the house breakers.

The 200w inverter came with some sunforce panels I bought a couple years ago. I cut off the cigarette lighter connector and used ring terminals and connected it to the battery. Is it possible the inverter is defective? Is 200w inverter the right thing for me to use?

Thanks for your help,
Courtk

[inetdog]

Hi,
I have two 100 Watt Renogy panels and one group 27 deep cycle battery. I have a 20 amp MPPT charge controller. Per my kill-a-watt meter, my AC devices are using 9 - 11 watts, 123 - 124 volts and about .14 amps. I have romex running about 30 yards from the shed with the solar panels to a chicken coop where the AC devices are (two foscam cameras, digital daylight timer for the coop door motor and two led lights with one being on a motion sensor). I'm trying to troubleshoot my 200 watt inverter because the alarm is going off as soon as I plug in the devices. However, if I plug a lamp directly into the inverter, it works fine. I have not tried the lamp plugged in for too long, just a minute or two. When I use my sunforce 1000 watt inverter, it seems to be working fine and the AC devices are working. It is my understanding that I should be using a smaller watt inverter, like the 200, to be more efficient. Also for troubleshooting, I'm able to plug the AC devices into an AC extension cord and it does not flip the house breakers.

The 200w inverter came with some sunforce panels I bought a couple years ago. I cut off the cigarette lighter connector and used ring terminals and connected it to the battery. Is it possible the inverter is defective? Is 200w inverter the right thing for me to use?

Thanks for your help,
Courtk

The power supplies you are using probably use a rectifier input to a capacitor, followed by a DC-to-DC converter (switching power supply)
One problem that you get with this kind of power supply is that the peak current at the top and bottom of the AC waveform is much higher than the average current.
As a result, the input that the inverter is pulling from the battery at that same instant is much higher than the average DC and is pulling the voltage down to the inverter cut-off level. Or else the inverter simply thinks that the load is too great because of the peak current.

Is the inverter at the shed, close to the batteries?

Can you try plugging your loads into the AC of the inverer one at a time to see whether the effect is cumulative under normal load or is just happening when you apply power suddenly to all of them?
If it is the latter, some sort of soft start circuit or filter on the AC line may help.

[blacksox]

The inverter is at the shed with the batteries.

I haven't had time to plug all the devices in, one at a time, yet, but I did plug in one of the cameras for about five minutes with no issues. I will try the rest of the devices this weekend.

Thanks for your help and I'll report this weekend.

[blacksox]

I had everything disconnected (two cameras, two led lights and a motor) except the Honeywell digital timer, but the inverter still triggered an alarm soon after plugging in the circuit. So, I bought a new Powerbright 200 watt inverter and it seems to work fine. I read on the new inverter that there is a 50 foot limit to the powered devices. I'm past that and it still works. I wonder if the original inverter had issues with the devices being too far.

[SunEagle]

I had everything disconnected (two cameras, two led lights and a motor) except the Honeywell digital timer, but the inverter still triggered an alarm soon after plugging in the circuit. So, I bought a new Powerbright 200 watt inverter and it seems to work fine. I read on the new inverter that there is a 50 foot limit to the powered devices. I'm past that and it still works. I wonder if the original inverter had issues with the devices being too far.

Well running wires a long way will cause the voltage to drop which may be an issue. Using a small wire gauge can also cause the voltage to drop.

Or maybe since the inverter is a low cost modified sine wave type it doesn't like electronic loads or is just a lemon.

Hopefully your new powerbright 200 will do the job for you.

[Sunking]

If I understand correctly I think I know what the problem is. Your inverter has a built-in Ground Fault Circuit Interupter. Although you may not have a fault, one of the pieces of equipment is inducing current on the EGC, thus tripping the circuit.

Normally I would not recommend this but give it a try for trouble shooting. Go to the hardware store and buy a 3-wire to 2-wire plug converter.

[blacksox]

The three to two plug adapter worked with the original 200 watt inverter. Is this an indicator that the circuit is not grounded? If yes, should I be grounding the circuit?

I have another issue now. I think my Honeywell programmable switch does not work with the 200 watt inverter, which is a modified sine wave. The symptoms are, there is no display on the switch when using the 200 watt but there is a display when using the 1000 watt pure sine wave inverter. Before I buy another inverter I was hoping someone could confirm the symptoms match a sine wave issue. I'm also assuming that since my system is only using 9 watts that a 1000 watt inverter is a big waste of energy. Using the 1000 watt inverter, the battery will usually drain by morning.

Thanks

[inetdog]

The three to two plug adapter worked with the original 200 watt inverter. Is this an indicator that the circuit is not grounded? If yes, should I be grounding the circuit?

I have another issue now. I think my Honeywell programmable switch does not work with the 200 watt inverter, which is a modified sine wave. The symptoms are, there is no display on the switch when using the 200 watt but there is a display when using the 1000 watt pure sine wave inverter. Before I buy another inverter I was hoping someone could confirm the symptoms match a sine wave issue. I'm also assuming that since my system is only using 9 watts that a 1000 watt inverter is a big waste of energy. Using the 1000 watt inverter, the battery will usually drain by morning.

Thanks

It is quite likely that the high frequency harmonics from the square edges of the inverter output are more than the power supply can handle and are getting into the DC output and causing problems. Or else the voltage regulation is not right and is keeping the programmable switch from running.
Some programmable switches also use the zero crossing of the sine wave as a timing source, which could be a greater problem with Modified Square Wave than with Pure Square Wave.

You could certainly use a very small Pure Sine Wave inverter just to power that switch (and its load?)

[blacksox]

I bought the cheapest pure sine inverter I could find and now the programming switch works along with the other loads. Yeah! Chickens can come out of their coop just before sunrise and they better get back in just after sunset, because the door is automatic now, pending I don't get more than two days of no sun.