Modifying a RCT2000VA UPS with an External charger

KOPITE

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Ok, so I am opening a new thread as nobody has done this and we looking for people in telling me and others how to do this.

Questions
Do we just disconnect the charger from the ups?
Do we connect the external charger to the ups?
Or can we have both the ups and external charger connected the the batteries without damaging the ups and disconnecting the internal ups charger at the same time.

Anyone with experience in these can gladly assist us. Any videos on how to do it. How does the charger look and disconnecting it maybe by soldering it.
 

The_Unbeliever

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First off, I used an RCT 600Va UPS as test.

I soldered a cigarette lighter plug and long cable to the internal battery. Ran it flat first (used the UPS till it cut out due to flat battery).

Then I plugged it into my car's cigarette lighter, hoping to charge the internal battery. It did not charge. Neither did it charge when I drove around for a while. Maybe the transformer (or charging circuit) is interfering with the charging. Will have to modify it so as to have the battery totally separated from the transformer and charging circuit.

So that avenue is out for now, will revisit it later.

FWIW it is not easy separating the charging circuit and the inverter circuit on some models. Will open this 600Va UPS again and see what I can do regarding the separation of charger and inverter circuits.

Currently I'm looking at procuring a solar panel with voltage regulator to charge the battery, but that will have to wait till I have funds.
 

spiff

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good question OP - I've just bought a 660w UPS to keep my tv, dstv & led light working till I can plug in my PSW inverter with 100amp battery.

would be nice to just add more Deep Cycle 100amp batteries at will.
 

KOPITE

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The_Traveller

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I have done the same man, I am looking for someone that has disconnected their internal charger and connected an external charger.

You seem to be missing the point here.

I don't think its a DIY thing. I would recommend you find an engineer in this field and let him do the necessary mod.
 

Joe_Moer

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OK, this is how I ran a similar setup at work for a couple of years without any problems. The extra battery pack (12V or 24V depending on your UPS) is connected in parallel to the UPS internal pack via the normally open contacts of a 220 Volt relay. The relay is fed from the mains supply, thus as long as there is mains the extra batteries are disconnected from the UPS internal battery pack. The ups chargers its own battery pack and the external pack is connected to a separate charger. When the mains fails the relay drops out and connects the external pack to the internal pack and Bob's your Auntie.
 

The_Unbeliever

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By the by, if the UPS' beeper/buzzer is driving you crazy, a blob of prestik [-]inserted[/-]forced into the beeper/buzzer do wonders... :whistling:
 

KOPITE

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OK, this is how I ran a similar setup at work for a couple of years without any problems. The extra battery pack (12V or 24V depending on your UPS) is connected in parallel to the UPS internal pack via the normally open contacts of a 220 Volt relay. The relay is fed from the mains supply, thus as long as there is mains the extra batteries are disconnected from the UPS internal battery pack. The ups chargers its own battery pack and the external pack is connected to a separate charger. When the mains fails the relay drops out and connects the external pack to the internal pack and Bob's your Auntie.

You still not giving us the answer we want
 

AfricanTech

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I have done the same man, I am looking for someone that has disconnected their internal charger and connected an external charger.

You seem to be missing the point here.
Jammer

I missed the point entirely
 

Joe_Moer

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You still not giving us the answer we want

I thought I answered this
"Or can we have both the ups and external charger connected the the batteries without damaging the ups and disconnecting the internal ups charger at the same time."
You will find it very difficult to disconnect/ disable the internal charger as it is usually integrated on the same board as the UPS circuit.
 

spiff

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OK, this is how I ran a similar setup at work for a couple of years without any problems. The extra battery pack (12V or 24V depending on your UPS) is connected in parallel to the UPS internal pack via the normally open contacts of a 220 Volt relay. The relay is fed from the mains supply, thus as long as there is mains the extra batteries are disconnected from the UPS internal battery pack. The ups chargers its own battery pack and the external pack is connected to a separate charger. When the mains fails the relay drops out and connects the external pack to the internal pack and Bob's your Auntie.

thanks for the tip - got my company electrician working on it as we speak.

what he suggested to me about the "CHARGING OF MULTIPLE EXTERNAL BATTERIES" is to get a timer of some sort that will allow the charger to charge each individual battery via relays for a given period eg. in my case 6hrs each.
 

KOPITE

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I thought I answered this
"Or can we have both the ups and external charger connected the the batteries without damaging the ups and disconnecting the internal ups charger at the same time."
You will find it very difficult to disconnect/ disable the internal charger as it is usually integrated on the same board as the UPS circuit.

If someone can confirm that I can charge the batteries while the ups is connected then I will be very happy
 

The_Unbeliever

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thanks for the tip - got my company electrician working on it as we speak.

what he suggested to me about the "CHARGING OF MULTIPLE EXTERNAL BATTERIES" is to get a timer of some sort that will allow the charger to charge each individual battery via relays for a given period eg. in my case 6hrs each.
Sometimes the simplest solution... :D
 

The_Unbeliever

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If someone can confirm that I can charge the batteries while the ups is connected then I will be very happy

As long as the external charger will not overcharge the batteries, but switch into trickle mode, then you should be OK.

I don't know about whether the UPS manufacturer designs their UPS'es to stop charging/trickle charge their batteries once full, but common sense says it should trickle charge once full, otherwise you'll get a lot of unhappy batteries which'll tend to do Funny Things, and that is Things You Most Certainly Do Not Want....
 

thehuman

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If someone can confirm that I can charge the batteries while the ups is connected then I will be very happy

My apc ups was happy with my external charger conected
I found id add the ups charging current and external charging current . But both stoped when battery full
 

thehuman

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My apc ups was happy with my external charger conected
I found id add the ups charging current and external charging current . But both stoped when battery full

I am about to try running 2 ups's from one battery pack :)
 
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