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Improve Capital Utilization through Reduced Battery Replacements

Battery Life Calculator

Batteries have a limited number of discharge-charge cycles before they lose capacity and must be replaced.  For this reason, one attempts to minimize the number of times a battery system is called upon to support a load.

The problem is that periodic generator tests cause momentary outages and/or power disturbances that require the battery system to take over.  Few realize that these tests cause such large reductions in battery life.

What do you do?  Stop generator testing?  You could, but that is unwise (and possibly against codes and standards).  But without periodic testing you won't have the assurance that emergency generator power will be available when needed.

The solution is to use a special type of transfer switch called a "Soft-Load Transfer Switch".

Since Soft-Load transfer switches are more expensive than conventional open or closed transition switches, we must determine if their use is justified.

Use this calculator to determine if a Soft-Load transfer switch is justified.  This calculator computes the relative reduction in battery system capacity based on how frequently a generator test is performed.  This loss of battery life does not occur when using a Soft-Load transfer switch.  Use this calculator to see if this recovered money more than pays for the difference in cost between a conventional transfer switch and a Soft-Load transfer switch.

1.  Select the system that best describes your engine generator.
                 (Single Engine)                 (Multiple, Paralleled Engines)










2. How frequently are your generators tested under load?
 times per

3. How often do you switch to generator power during storm warnings?

4. Select the battery type used in your UPS or DC power plant:

5.  Battery system size (fill in what you know):
    volts (e.g. 24, 48, 125, etc.)
    amps (e.g. 100, 300, 600, etc.)
    total VA (e.g. 2000, 4000, 10000, etc .)
    hours of capacity at rated load (e.g. 0.25, 1, 8, etc.)
Note: For most accurate payback calculation, include the total VA capacity of all battery systems that are charged by this generator including under-desk UPS and rechargable batteries used by automation devices.

6. Cost to replace battery system:
  Not sure (select this and we will compute using typical costs based on
          industry averages and based on the battery size and type listed above)

7. Type of transfer switch between generator and battery system:
 Open Transition (if you don't know, it is probably Open Transition)
 Open with In-Phase Monitor
 Closed Transition
 Soft-Load (Zero Power) Transfer



Battery Life
Read the complete application note on why battery life is affected during generator testing. 

Transfer Switches
Learn more about Soft-Load Transfer switches, Peaking Switches and other battery saving technologies along with our complete family of conventional transfer switches

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