Statpower (Now Xantrex) Prowatt 1500 inverter shuts down

[Ray]

I have a Statpower Prowatt 1500 Inverter that will fire up for about 2
seconds with enough power to light up all my lights (At least 300 Watts)
Then it shuts down with the overload light on.

I have replaced this unit with a prowatt 1750, as Xantrex has no repair
facility or repair info available. I had hoped I would be able to some
comparison checking to determine what is wrong with the old one, but they
are too physically different.

Has anyone any info, even a block diagram of how the inverter works ?
Especially the shut down circuit.
Even a generic schematic might help.
I dont think there can be much wrong, as it fires up for 2 seconds..

R

 

Ray <argyle1@hotmail.com> wrote:

I have a Statpower Prowatt 1500 Inverter that will fire up for about 2
seconds with enough power to light up all my lights (At least 300 Watts)
Then it shuts down with the overload light on.

If you reduce the load to 100 W or even 50 W, does the inverter stay on
for longer? If it uses sealed lead-acid batteries (gel cells), and the
batteries are over 5 years old, they are most likely junk. Between 3 and
5 years old, they might be junk. Fortunately these batteries come in a
standard-ish range of sizes from several manufacturers; I have had good
luck with Panasonic and Power-Sonic gel cells.

If you're unsure about the battery, the simplest test is to disconnect it
and measure its voltage. Around 6.3 V (6 V nominal) or 12.6 V (12 V
nominal) is probably pretty good. Down to maybe 6.0 V or 12.0 V might be
salvageable. If it's way lower than these, like less than 4.0 V or 8.0 V,
the battery is junk. If you think the battery might be salvageable, hook
it back up and leave the inverter plugged into the wall but not powering
anything for a day. Then disconnect the battery again and check the
voltage. If it came up significantly, there is hope, but if not, get
some new batteries. You might try measuring the battery voltage while
the inverter is starting; if it drops too low the inverter will shut
itself off. This may be difficult to do in the short time you have;
another test is to take the battery out of the UPS and load it with
something like a car tail light bulb to see what the voltage does. The
on-load voltage will always be a little less than the no-load voltage,
but if you use a typical tail light bulb (about 2 A) and get 12.6 V
no-load and less than about 11.5 V on load, the battery is probably
toast.

Be careful when fooling with inverters; they are designed to make
line/mains voltage at a fair amount of current.

Matt Roberds

 

[Ray]

The inverter stays on for 2 seconds no matter what the load. The
batteries are fine, as stated, a new inverter works fine on the same
batteries.

I have a fair amount of experience with electronics, just need some
pointing in the right direction.

R

If you're unsure about the battery, the simplest test is to disconnect it
and measure its voltage. Around 6.3 V (6 V nominal) or 12.6 V (12 V
nominal) is probably pretty good. Down to maybe 6.0 V or 12.0 V might be
salvageable. If it's way lower than these, like less than 4.0 V or 8.0 V,
the battery is junk. If you think the battery might be salvageable, hook
it back up and leave the inverter plugged into the wall but not powering
anything for a day. Then disconnect the battery again and check the
voltage. If it came up significantly, there is hope, but if not, get
some new batteries. You might try measuring the battery voltage while
the inverter is starting; if it drops too low the inverter will shut
itself off. This may be difficult to do in the short time you have;
another test is to take the battery out of the UPS and load it with
something like a car tail light bulb to see what the voltage does. The
on-load voltage will always be a little less than the no-load voltage,
but if you use a typical tail light bulb (about 2 A) and get 12.6 V
no-load and less than about 11.5 V on load, the battery is probably
toast.

Be careful when fooling with inverters; they are designed to make
line/mains voltage at a fair amount of current.

Matt Roberds

 

[Mark]

the inverter i have will shutdown for several reasons including:

1) low input voltage
2) ground fault at the output

the ground fault is a strange one, the inverters actually produce a
voltage on both the hot and netral output and if there is any fault
form either the hot or neautral to the ground pin, the inverter will
shut down, it does this by using a small resistor in series with the
ground lead and if it senses any small voltage across this resiostor
it will shut down.

I wold check the low voltage and ground fault sensing circuits..
Mark