When installing a new backup generator or uninterrupted power supply (UPS), many businesses still wrongly believe that factory performance testing before the equipment is shipped is enough to ensure reliable operation once installed.
Here, we explore why this is not the case, and offer best practice advice for ensuring power resilience through regular testing of your backup generator power system.
- The impact of onsite conditions
Factory conditions do not replicate the environment found onsite. It is, therefore, vital to consider variables such as climate, humidity and temperature differences, and how these will affect the performance of your UPS and backup power system once in-situ.
Even simple fluctuations in temperature can affect run time performance, battery capacity, cut off voltage, gassing and thermal runaway in UPS systems. Humidity and climate fluctuations can also cause longer-term performance issues including corrosion and condensation.
- Factory conditions are rarely replicable
When tested at the factory, your backup generator will undoubtedly have been put through rigorous testing. However, even with the very best of testing, the fuel supply system, exhaust system, and cooling will differ from the system used in operational conditions. Equally, it won’t have been connected to your specific electrical system, with its own array of circuit breakers, instrumentation, and automatic changeover switches. The fact that the genset now has to operate to capacity with all these different supplying factors is reason enough to test at commissioning regardless of how recent a factory test was performed.
- The impact of transportation and installation
At the point of factory testing, your equipment has been subjected to very little movement or human intervention. It has been constructed in a carefully controlled environment and handled with the utmost care. But by the time it reaches the point of installation, this sensitive equipment has been lifted, transported, installed, commissioned, and adjusted by human hands. Any one of these processes may throw performance off kilter. Again, the impact may not be visible straight away. For this reason, it is critical that power systems are tested in-situ, regularly and for backup power, this means using a load bank.
Testing backup power using a load bank
A load bank is used to create an electrical load that imitates the operational or ‘real’ load that a backup generator would use in normal operational conditions. In short, load banks are used to test, support, or protect a critical backup power source and ensure that it is fit for purpose in the event that it is called upon.
Ideally, all generators should be tested annually for real-world emergency conditions using a resistive-reactive 0.8pf load bank. Best practice dictates that all gensets (where there are multiple) should be run in a synchronised state, ideally for 8 hours but for a minimum of 3.
Where a reactive-only load bank is used, testing should be increased to 2-4 times per year at 3 hours per test. In carrying out this testing and maintenance, fuel, exhaust and cooling systems and alternator insulation resistance are effectively tested and system issues can be uncovered in a safe, controlled manner without the cost of major failure or unplanned downtime.
Secure power resilience for your facility
For more information on using a load bank to ensure power resilience for your facility, contact our team here.