Chapter 1 Introduction
3
The double DSP and MCU form the full digital control system to realize the powerful
function of the UPS. The switching between the operation modes is realized by
controlling the bypass static switch and the inverter static switch. Advanced battery
management prolongs battery life.
Multi-communication ports and management software make it possible for the
customer to monitor the UPS performance locally or remotely. The Liebert UPS
uses full digital, discrete and on-line parallel operation technology. In parallel
operation, several UPS units input parallel logic signals and cross current detection
signals through parallel operation boards to enable a maximum of four UPS units to
operate in parallel. (N+X) redundancy parallel operation, capacity expansion and
hot-standby configuration can be realized. If an additional UPS is required to be
added to the system, no auxiliary equipment is required and power to the load
need not be interrupted.
1.4 Structure and Layout
The structure and layout of the system is shown on Figures 1-3 and 1-4. The
system consists of the rectifier, inverter, auxiliary power supply, input and output
power distribution, monitoring system, parallel control system, lightning protection
unit, EMI filter, fan and input and output isolation filters.
1:Fan 2:rectifier 3:two auxiliary power supply boards ULW2L61M5
4:contactor 5:battery input terminals 6:circuit breaker Q3BP for maintenance
7:Inverter 8:Power distribution board ULK2L61R1
9:D level lightning protection device SPD12Z
10: Output circuit breaker Q5 11:rectifier input circuit breaker Q1
12:bypass input circuit breaker Q2 13:operation keypad board ULW2L61K1
14:LCD 15:parallel board ULW2L61M3
16:monitoring board ULW2L61U2 17:4 leveling feet (M20)
Figure 1-3 Components of 20/30kVA UPS