Vertiv Liebert EXS 80kVA UPS, User Manual

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Vertiv™ Liebert EXS 80kVA UPS User Manual
1 Overview
Parallel redundancy mode (system expansion)
For higher capacity or higher reliability, the outputs of multiple UPS modules can be programmed for
directly paralleling while a built-in parallel controller in each UPS module ensures automatic load sharing.
The parallel system can be composed of up to four UPS modules. For the operation principle diagram of
the parallel redundancy mode, see Figure 6-1 .
Frequency converter mode
The UPS can be programmed into frequency converter mode for either 50Hz or 60Hz stable output
frequency. The input frequency may vary from 40 Hz to 70 Hz. Under this mode, it is required to open the
maintenance bypass switch to disable the bypass operation, and the battery becomes optional depending
on any requirement to operate in battery mode.
LBS mode
A dual bus system consists of two independent UPS systems, each containing one or more parallel UPS
modules. The dual bus system has high reliability and is applicable to the load with multiple inputs. For
single-input load, an STS can be installed to power the load. For the operation principle diagram of the LBS
mode, see Figure 6-4 and Figure 6-5 .
1.5 Battery Management
The following battery management functions are set by the service engineer through the Vertiv setting
software.
1.5.1 Normal Function
1. Constant current boost charge
Adopt the constant current (within battery charging limit) to charge the battery. The function can be used
for battery capacity fast recovery. The charge current can be set.
2. Constant voltage boost charge
Adopt the constant voltage to charge battery. The function can be used for battery capacity fast recovery.
For VRLA batteries, the maximum boost charge voltage should not exceed 2.4V/cell.
3. Float charge
The charging method is used for keeping battery with a full capacity. The float charge voltage is generally
low. The function can balance the capacity loss due to battery self-discharging, and can be used for
battery capacity recovery.
For VRLA batteries, the float charge voltage should be between 2.2 V/cell and 2.3 V/cell.
4. Automatic transfer to float charge
When the charge current is less than 'Threshold of Equalize Charge to Float Charge' or 0.5A, the charger
will automatically transfer from boost charge to float charge. When boost charge time exceeds the limit of
'Equalize Charge Protect Time Limit', the charger will be forcibly transferred to float charge for protecting
the battery.
5. Float charge temperature compensation (optional)
This function must be used together with the battery temperature detection device. The Vertiv battery
temperature sensor is a standard option for your selection.