Battery and Battery Charger

the trickle charging and the boost charging currents depend on Battery characteristics.One has to see the recommendations given by the battery manufacturer.If you could let me know the make of the batteryand type of battery, i can suggest the trickle charging current nd boost charging currents.

Thank you sir for your kind co-operation.The battery manufacturer is EXIDE and type of battery is VALVE REGULATED LEAD ACID POSITIVE TUBULAR TYPE.

Dear Debika

VALVE REGULATED LEAD ACID BATTERY IS DIFFERENT FROM TUBULAR LEAD ACID BATTERY. VRLA battery is SEALED MAINTENANCE FREE AND TUBULAR LEAD ACID BATTERY is one in which electrolyte is externally poured. For the same application, depending on the load profile, DIFFERENT capacity of battery may be required. Furthermore chargers for both types of battery are different. As already requested, pls. send separate mail directly to me. There are lot of other requirements, which may be inappropriate to be discussed in an open forum, as others may not be too interested.

Thanks

Ashok Toshniwal, Bangalore, India

I do not understand what is meant by "lot of other requirements which may be inappropriate to be discussed in open forum as others may not be too interested"

We become members into the forum and exchange notes to learn more and get to know the latest advancement in the industry.

There is no harm in yourselves revealing the details .Members are very much interested to know about the latest developments and upgrade their knowledge.

Dear Ram

It is good to know, that there are knowledgeable individuals who are also willing to add something on every issue. You have rightly mentioned the trickle charging current but that alone will not help in suggesting the right configuration. Generally for similar applications, Float & Float cum boost chargers are used but lot of people prefer a DUAL Float cum boost charger. In the absence of load current details, float charger cannot be sized since float charger feeds the load and trickle charges the batterx. Furthermore With all regards to everybody I donot wish to undermine others knowledge and information as well.

From Debika's mail it is not clear which type of battery she has selected. Other important requirement in battery & charger sizing is the LOAD PROFILE which comes on the battery when AC supply fails. I presume that the 2x25 MW power project is steam turbine based and thus an EOP motor will also come in. This is DC operated motor coupled to a pump to cool the turbine rotor & generally runs through the same battery. Feeder requirement will therefore be different for different rating of motor. Then is there a DC operated emergency lighting also required , if yes then additional interlocking with AC supply is required. To complete the DC system, DCDB is also required. What are the details?

What are the faults to be annunciated, whether any transducers are required for remote monitoring etc. etc.

Thus since there are quite a few details required for giving the right solution. Trust you would agree to this & hence the particular statement. But at the same time, I am glad that there is somebody who is genuinely interested in knowing greater intricacies on this issue.

Thanks

Ashok Toshniwal, Bangalore, India

I was also manufacturer of Battery charger, and supplied Chargers to many Industries.

Since the Guest wanted the charging currents on triclkle and boost mode I had indicated the same.

Generally we prefer to give charger seperate and DC power source seperate.In case of power failure the Battery will feed the DC load, with a auto change over scheme.

Since the Guest did not wanted advise from us about the procurement I have not given the particulars and I have restricted my exposure by giving the details what he wanted, since this forum is not for promoting our products manufactured by us.

Dear Sir,

As I have calculated,the current has come in float mode 106A and in boost mode 263A.So u please provide me ur detail calculation.How u have calculated current.If u want to ask me something please ask.......

The Currents indicated is only for battery charging, without taking into effect the DC Load.

I do not know how you have arrived at the current of 106 ampsand 263 amps.

Now I have arrived to the final value.The issue is going to be closed.The battery sizing has been changed to 1100AH at 1 hour rate and the charger current will be 150A for trickle charging and 200A for boost charging

Dear Debika

What a co-incidence, day before yesterday I have sent an offer to one of our customer for 110 V 1000 Ah SMF battery with 150 A Float charger + 200 A Boost charger ( which can also operate in float mode by a separate selector switch ) & DCDB for installation in a 25 MW power plant.

I feel it is inappropriate to discuss personal business matters on this public forum and therefore please send your requirements separately to me.

I look forward to same.

Thanks and regards

Ashok Toshniwal, Bangalore, India .

For a 1400 Ah battery, trickle charging current minimum would be 1.4 Amps and maximum would be 5.6 amps

Starting rate of charging current would be 196 amps and that of finishing rate of charging current would be 98 amps.

Therefore the battery charger which you are looking for should satify the above currents .

Dear Debika

We regularly manufacture battery chargers for power plants, substations etc. and supply with battery. Our customers include leading EPC companies, steam turbine manufacturers etc. We have installations in India and abroad as well. Kindly send separate mail so that we could discuss the issue further.

Thanks

Ashok Toshniwal, Director - Universal Instruments manufacturing Co. Pvt. Ltd., 268A, 4th phae, 1st cross, peenya industrial area, Bangalore ashoktoshniwal @yahoo.com

Hello ,

The fool proof method of selecting charging cureent is AH / 10 as 10 hour rate of charging and select a higher rate charger as 250 a charger and select trickle current as fool proof is 1 milli amp per AH so select as 5 amps as trickle current .if aged the batteries the trickle current may enhance up to 3 mili amp per AH.all above are fool proof method better to check the manufacturers recommenttions.