Disabling charge circuit

[BillP]

I Am using a 5000 unit as an inverter in my pv array system. I use a outback 80 as the battery charge controller for my battery banks. I would like to disable the charging circuit in the ups. Can anyone assist?

[Anonymous user]

Based on  my understanding of the internals of APC smart-ups, what you are asking is impossible. The inverter/charging circuits are tightly integrated under the control of not only one very complex ASIC (application specific integrated circuit) called the "Bridge Charger" ( This ASIC controls pretty much everything that goes on in that functional block of the UPS...controlling the inverter, regulating the charging hi/lo, etc), but furthermore the Bridge Charger is in turn controlled by the main UPS microprocessor with associated DSP circuitry. You cannot simply separate out the charging function as one unit and defeat it. You are more likely to blow the ups up (and possibly yourself with it) if you try to mess with these circuits/architecture.

Save your pennies for a real inverter they can be had for around $500 or less based on ebay listings I just read.

10000w Peak 5000 Watts Pure Sine Wave Power Inverter DC 24V AC 220V 60Hz | eBay

[voidstar_apc]

I have to agree with Battman. On a line interactive SmartUPS, the inverter is the charger. You might be able to find logic signals that control charging behavior, but maybe not. Other people on this board have managed to change the float voltage.

[wayne_i_apc]

It sounds like you want to use the UPS as a transfer switch (but NOT as a UPS) when you choose to use utility power, or as an inverter when you choose to use your solar array. Could this be accomplished by putting the UPS into bypass? I know bypass mode passes utility power directly to the UPS output and disconnects the inverter output, but does it also disable the charger circuit? Of course, if there was a failure of utility power, any connected load would loose power in this configuration, and I defer to others what you would need to do to execute a "cold start" to bring the inverter online when you disable utility power to use your "off-grid" source, or after being left in bypass when utility power went out. And I know the larger UPSs also have 2 methods for bypass, a manual (I believe "maintenance" or "static") bypass, and a UPS (software) controlled bypass. Someone correct me if I'm wrong, please! I don't know if your UPS has the manual bypass.

The other option would be an external (commercial) transfer switch which would permit you to select either raw utility power or the output of the UPS as a source for your load. In that configuration you would simply leave the utility input to the UPS disconnected and cold start the unit when desired.

Either way, your goal of having it timer controlled is a completely different can of worms!

As others have said, you've got an expensive unit (well ok, free to you!) and you only want to use about half it's functionality...

[BillP]

I Am using a 5000 unit as an inverter in my pv array system. I use a outback 80 as the battery charge controller for my battery banks. I would like to disable the charging circuit in the ups. Can anyone assist?

[BillP]

Can you clarify the exact model of the UPS? I believe the answer will be no but I'll have to verify depending on the model.

This is usually found on a white sticker on the back or bottom of the UPS.

[Anonymous user]

It sounds like this user is referring to a Matrix 5000 ?  Perhaps he is connecting the solar panels up to the 48 volt Anderson battery connector at the rear and using the ups as an inverter by starting it up offline...

[BillP]

Smart-UPS XL 5000 RM 7U 208V In 208/120V Out

[BillP]

SSolar panels connect to the outback charge controller. Charge controller connected to 48 v battery bank. Ups connected to Abattery bank through nderson connector.

[BillP]

USing ups as inverter continuos duty. When I activate220 v to ups it draws 400watt to charge battery. Charge battery not required from ups.

[Anonymous user · Accepted solution]

You are still going to require standby battery charger, otherwise, how do you maintain proper float voltage of the 48 v battery string when there is no solar input (night time, cloudy days for long periods) ?  Disabling the charging circuits in a smart-ups requires schematic ( proprietary ) and extensive understanding of UPS design ....you are likely better off just buying a standalone inverter ?