Modifying a RCT2000VA UPS with an External charger

[thehuman]

That charger will never stop will always stay at that voltage . Will only go lower if battery very flat
Current meusure . Google how to do it will find some nice youtube videos

 

[KOPITE]

That charger will never stop will always stay at that voltage . Will only go lower if battery very flat
Current meusure . Google how to do it will find some nice youtube videos

It's on 27.3v now

 

[BigEars]

KOPITE. Only used batteries draw any meaningful current available. So...fully charged is very little current.
So you can either decide 1....loadshed yourself tonight for 2hours. Then check with you new Ampmeter what your internal UPS CHARGER can give..
2. Wait for the next loadshedding and do as above.

This.is.why.I.hate.trying.to.explain.tech.stuff.over.the.net

Makes me tired

 

[KOPITE]

im using a 1200 with 2 deep cycle marine batteries.
the batteries are charged by the UPS unit and a supplemental 20 amp 13.8 volt dc power supply.
the float voltage between the UPS and the external power supply have been matched and diodes have been placed to isolate the UPS charging circuit from the external power supply and vice versa, in case there is differential voltages and current during the charge.
it would have been easier to disable the charging circuit in the UPS, but this was too difficult to do.
the charging circuit in the UPS does not have enough current to charge 2 deep cycle marine batteries and during the charge, the unit will go into thermal protect from over current draw.

Quote

 

[BigEars]

^^^and ??

Simple things become complicated...
Why is it always so?

/shrugs shoulders and walks away for now

 

[KOPITE]

KOPITE. Only used batteries draw any meaningful current available. So...fully charged is very little current.
So you can either decide 1....loadshed yourself tonight for 2hours. Then check with you new Ampmeter what your internal UPS CHARGER can give..
2. Wait for the next loadshedding and do as above.

This.is.why.I.hate.trying.to.explain.tech.stuff.over.the.net

Makes me tired

Will do this at next loadshed

 

[thehuman]

Will do this at next loadshed

Just go read up how to use amp meter on a multimeter . You can blow up some meters if you short battery out with meter

 

[KOPITE]

Good read on battery chargers
http://www.sens-usa.com/en/products/battery_chargers_product_faq

Float charging Voltage
13.6 to 13.8 VDC/unit Average at 25oC

Recommended Maximum Charging Current Limit
30A

Equalization and Cycle
14.6 to 14.8 VDC/unit Average at 25oC

Service Self Discharge
RITAR Valve Regulated Lead Acid (VRLA) batteries can be stored for more than 6 months at 25oC. Self-discharge ratio less than 3% per month at 25oC. Please charge batteries before using.

 

[ryanrich]

No one is saying it won't work - frankly, it will work just fine... Initially.

If you want your batteries to only last 6 odd months, then go right ahead and do this. If you want your batteries to last (as long as they possibly can), then you need to treat them with the respect and proper maintenance that they require.

I'm sure you are aware of the cost of batteries, and if you can afford to fsck them up and replace them constantly, go for it

Guy here at the office I got the idea from has been running the same setup for 6 months now and the batteries are still perfect. The RCT 2000 actually has a very good charger that alloys easy scaling to cater for external batteries. My 10x 26Ah batteries drop to around 75% after a two hour load shed in the evening with all my stuff running and charge back up to 100% by morning.

 

[southafricanrob]

Hey guys been following this thread with interest... 2 quick questions:
Does this UPS run okay on a generator and will it charge up as per on mains?

And I have 2 PC's that need powering - they're quite far a part so wondering if better to get 2 smaller UPS (say 2 of the RCT100VA) or use the big one a run a lead. ie do you get economies of scale with a bigger one and does a bigger load kill the batteries faster than 2 smaller loads / UPS's.

Thanks

 

[savage]

Hey guys been following this thread with interest... 2 quick questions:
Does this UPS run okay on a generator and will it charge up as per on mains?

And I have 2 PC's that need powering - they're quite far a part so wondering if better to get 2 smaller UPS (say 2 of the RCT100VA) or use the big one a run a lead. ie do you get economies of scale with a bigger one and does a bigger load kill the batteries faster than 2 smaller loads / UPS's.

Thanks

Yes - If you have an adequate generator, it will power the UPS just fine. And no, rather get one big UPS instead of two small ones. High Voltage / Low Amperage (i.e. mains cables to plugs etc.) you really need not worry about voltage drops that much. The issue with voltage drops comes in when you have low voltage, high amperage (i.e. batteries) only.

 

[southafricanrob]

Yes - If you have an adequate generator, it will power the UPS just fine. And no, rather get one big UPS instead of two small ones. High Voltage / Low Amperage (i.e. mains cables to plugs etc.) you really need not worry about voltage drops that much. The issue with voltage drops comes in when you have low voltage, high amperage (i.e. batteries) only.

excellent - thanks

 

[KOPITE]

Just go read up how to use amp meter on a multimeter . You can blow up some meters if you short battery out with meter

Ok, so we off from 6pm till 8h30pm. Which is the correct setting on the meter

 

[thehuman]

See pic

 

[KOPITE]

Ok cool, where must I turn the knob to.

 

[KOPITE]

Ups charge is a dumb device
It keeps bat at a certain voltage
Next time you get loadsheding and the batteries are discharged meusure the charging current with the multimeter . For this to work need to set meter to current . Move the positive lead to the current connection , disconect one battery pole from battery and put one leed on disconected battery terminal and the other on the loose ups battery lead

Must the internal charger be charging when I do this or not. I have the batteries connected in series . I then disconnect the negative terminal from the one battery. Should I then put the red one of the multimeter on the positive of the connected battery and the black one of the multimeter on the loose cable that is supposed to be connected to the other battery.

 

[KOPITE]

I have set the red one the current on the multimeter. Then I moved the knob to the 10A sign on the multimeter. Is this correct or where should it be moved to test it correctly.

 

[KOPITE]

Check the voltage and it was 25.2v and it was on 71%

 

[KOPITE]

Ups charge is a dumb device
It keeps bat at a certain voltage
Next time you get loadsheding and the batteries are discharged meusure the charging current with the multimeter . For this to work need to set meter to current . Move the positive lead to the current connection , disconect one battery pole from battery and put one leed on disconected battery terminal and the other on the loose ups battery lead

Sorry for being so blonde with these things. But I'm not so clued up. I have set it correct on the multimeter, but your directions where I put the leads confuses me. Is this testing for one or 2 batteries in series. If this is for 2 batteries then you would mean I connect the positve terminal coming from the ups on the positive terminal to the one battery. I loose you from here on.

 

[thehuman]

http://m.wikihow.com/Measure-Amperage
http://www.sciencebuddies.org/science-fair-projects/multimeters-tutorial.shtml
Read that
Was out phone was flat