Could anybody help me understand the difference of these four different terminogies for a UPS battery? It sounds to me capacity test equals to performance test, modified performance test equal to service test. For switchgear battery for relay system, which test duration should be used? For power generation emergency or DCS batteries, what test duration should be used? Thanks a bunch!!!
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Battery capacity test, performance test, modified performance test, service test
- Thread starter leoliu
- Start date
MikeHalloran
Mechanical
For a lead-acid battery, the simplest test involves looking at the date code.
Replace the battery on its third birthday.
Every day after that involves a risk.
If you can't risk going black, there's your answer.
Mike Halloran
Pembroke Pines, FL, USA
Replace the battery on its third birthday.
Every day after that involves a risk.
If you can't risk going black, there's your answer.
Mike Halloran
Pembroke Pines, FL, USA
oldfieldguy
Electrical
Mike-
I assume that you're talking about VRLA "maintenance-free" ( I call them 'maintenance-proof') batteries and if so, I concur, although my company's practice stretches that out to five years.
For flooded-cell lead acid batteries, a load test is called for upon initial installation and every five years afterward. That time is revised downward if the test results are less than satisfactory. At 80% of nameplate, you should then consider replacement. If the string is less than ten years old (a nebulous figure) and you have one or two cells bad and the rest testing good, replace the bad cells (or jars) and continue service. Past that point, you'll likely find that deterioration is starting to appear on many cells and replacement of the entire bank is in order. Flooded cells can be measured and inspected visually through several commonly understood means.
I am in the middle of this exercise. One of my business units uses flooded cell banks for UPS. I am replacing strings that are over twenty-five years old. The other business unit favors the maintenance-free batteries and I just replaced one station's array that was seven years old with several bad cells. Mine are in three-cell and six-cell batteries and the cases are opaque.
On VRLA battereis, visual inspection seldom tells much and a failing cell can be masked by the readings of good cells in the unit. In batteries used in float service, a failed cell might not show up until the batteries are required to perform. The old IEE standard called for annual load tests of VRLA batteries. This is expensive for small banks.
old field guy
I assume that you're talking about VRLA "maintenance-free" ( I call them 'maintenance-proof') batteries and if so, I concur, although my company's practice stretches that out to five years.
For flooded-cell lead acid batteries, a load test is called for upon initial installation and every five years afterward. That time is revised downward if the test results are less than satisfactory. At 80% of nameplate, you should then consider replacement. If the string is less than ten years old (a nebulous figure) and you have one or two cells bad and the rest testing good, replace the bad cells (or jars) and continue service. Past that point, you'll likely find that deterioration is starting to appear on many cells and replacement of the entire bank is in order. Flooded cells can be measured and inspected visually through several commonly understood means.
I am in the middle of this exercise. One of my business units uses flooded cell banks for UPS. I am replacing strings that are over twenty-five years old. The other business unit favors the maintenance-free batteries and I just replaced one station's array that was seven years old with several bad cells. Mine are in three-cell and six-cell batteries and the cases are opaque.
On VRLA battereis, visual inspection seldom tells much and a failing cell can be masked by the readings of good cells in the unit. In batteries used in float service, a failed cell might not show up until the batteries are required to perform. The old IEE standard called for annual load tests of VRLA batteries. This is expensive for small banks.
old field guy
raithrovers1
Industrial
Capacity test: Discharging a battery according to the battery manufacturer's data sheet at a specific current for a specific duration.
Acceptance test: As above but for a brand new installation
Modified performance test: A test, in the “as found” condition, of battery capacity and the ability of the battery to satisfy the duty cycle. Example, if system has a load shed schedule then the discharge current for the battery should follow this schedule.
Service test: A test in the as “found condition” of the battery’s capability to satisfy the battery duty cycle. This is often considered as switching off the mains supply to a UPS and letting the battery discharge into the load (through the inverter) for the specified time that the UPS was designed to hold up on battery operation.
UPS Service Manager
Acceptance test: As above but for a brand new installation
Modified performance test: A test, in the “as found” condition, of battery capacity and the ability of the battery to satisfy the duty cycle. Example, if system has a load shed schedule then the discharge current for the battery should follow this schedule.
Service test: A test in the as “found condition” of the battery’s capability to satisfy the battery duty cycle. This is often considered as switching off the mains supply to a UPS and letting the battery discharge into the load (through the inverter) for the specified time that the UPS was designed to hold up on battery operation.
UPS Service Manager
- Thread starter
- #6
Thanks a lot for the information. I kind of get better idea.
For the switchgear battery in the substation, and emergency battery or control battery in power plants, generally performance tests are conducted to measure the capacity. The testing duration for power plant battery generally is 8 hours and the discharge rate is selected based on the manufacture table per 8 hours. right? but for substation battery, i found some literature say typically 3 hours but other say typically 15 minutes or 30 minutes. Could you please share your experience on the typical duration for switchgear batteries?
For data center UPS battery, I heard in generally service test or duty test is used. The discharge current is generally the load current as raithrovers1 said. the duration is about 15 or 30 minutes. Is my undrestanding correct?
Thanks a lot.
For the switchgear battery in the substation, and emergency battery or control battery in power plants, generally performance tests are conducted to measure the capacity. The testing duration for power plant battery generally is 8 hours and the discharge rate is selected based on the manufacture table per 8 hours. right? but for substation battery, i found some literature say typically 3 hours but other say typically 15 minutes or 30 minutes. Could you please share your experience on the typical duration for switchgear batteries?
For data center UPS battery, I heard in generally service test or duty test is used. The discharge current is generally the load current as raithrovers1 said. the duration is about 15 or 30 minutes. Is my undrestanding correct?
Thanks a lot.
MikeHalloran
Mechanical
>>>...i found some literature say typically 3 hours but other say typically...<<<
You are being lazy.
If you must refer to 'literature', please provide a link to it.
>>>Could you please...<<<
Remember you are asking busy professionals to help you, for free.
>>>Is my undrestanding correct?<<<
Go read it again until you understand it. We cannot detect the contents of your brain.
Mike Halloran
Pembroke Pines, FL, USA
You are being lazy.
If you must refer to 'literature', please provide a link to it.
>>>Could you please...<<<
Remember you are asking busy professionals to help you, for free.
>>>Is my undrestanding correct?<<<
Go read it again until you understand it. We cannot detect the contents of your brain.
Mike Halloran
Pembroke Pines, FL, USA
- Thread starter
- #8
Dear Mike:
If you don't like to reply, that is fine. That is your own business.I am not soliciting your free service at all. I certainly don't respect your "professional" by the way you reply.
As a matter of fact, I am having beeing reading the related document based on what I can get. True, I am not a expert in this area but try hard to understand it.
If you don't like to reply, that is fine. That is your own business.I am not soliciting your free service at all. I certainly don't respect your "professional" by the way you reply.
As a matter of fact, I am having beeing reading the related document based on what I can get. True, I am not a expert in this area but try hard to understand it.
An alternate test you may want to look at is an impedence test using Meggers BITE series (Other manufactures have something similar)
Also from Megger is this guide to battery testing that should clear some things up for you
Also from Megger is this guide to battery testing that should clear some things up for you
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