Pulsed Parallel Operation, Load Transfers | Liebert Series 600T

Also, if required for maintenance, the static switch can be isolated from the bypass line by opening (to the OFF position) the Static Switch Disconnects.

Pulsed Parallel Operation

When an overload condition such as magnetic inrush current or a branch load circuit fault exceeds the overload capacity of the connected modules, the static bypass switch pulses on for 40 milliseconds. This allows up to 1000% of the rated full load current from the bypass line to clear the overload without closing the bypass circuit breaker. The bypass source is briefly in parallel with the UPS system, permitting the bypass source to carry the initial overload current. If the overload clears before 40 milliseconds, a load transfer to bypass is not made. If the overload condition continues, the automatic transfer is made (maintaining the load voltage within the specified limits).

This pulsed static switch operation reduces nuisance operation of motor-operated circuit breakers for such short- term conditions.

Load Transfers

Transfers to (transfer) or from (retransfer) the bypass may be performed automatically or manually in a make- before-break sequence. This is accomplished through the overlapping operation of the UPS output and the sys- tem bypass power switching devices.

Manual load transfers and retransfers are initiated by the operator from the System Control Cabinet (SCC).

In a manual operation, or an automatic retransfer, the two motorized circuit breakers—UPS output and system bypass—are both closed simultaneously for a short period of time (overlap).

Automatic transfers are initiated by the SCC system control logic when an overload is beyond the specified capa- bilities of the UPS system or when a fault occurs within a non-redundant UPS module. An automatic retransfer is initiated if this function is enabled and if system conditions for a retransfer are present.

In an automatic transfer, the circuit breakers do not overlap, but during the short time gap bypass power is sup- plied to the critical load through the solid state static switch.

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Liebert Series 600T manual Pulsed Parallel Operation, Load Transfers

Contents

Series 600T UPS DIS Product Table of Contents Manual Procedures Figures Tables Important Safety Instructions Overview of this Manual System Description Multi-Module UPS, 65-80 kVA left and 100-500 kVA right Product Multi-Module 500-750 kVA UPS Types of System Control Cabinets SCCs System Control Cabinets SCCs Other Factors to Consider ReliabilityDesigned for Success Safety Precautions Modes of Operation Operator Controls DIS Product Options General Component Descriptions System Control Cabinet Battery Plant UPS Module Firmware Detailed Component DescriptionsControls Hardware Rectifier/Charger Input Circuit Breaker Input Power FactorBattery Charging Circuit Isolation Transformer Battery Equalize Charge Circuit Battery DisconnectBattery Charge Current Limiting Operation After End-of-Discharge Inverter Non-Linear Load CharacteristicsUnbalanced Load Characteristics Output Regulation and Overload Performance Fuse Protection Static Switch IsolationStatic Bypass Shorted SCR Monitoring Pulsed Parallel Operation Load Transfers Manual Transfers Transfer and Retransfer ConditionsAutomatic Transfers to Bypass Transfer Inhibited Retransfer Inhibited Redundant ModeManual Retransfers Features Display Screen and Operator Controls Description Function System Control Cabinet Operator Controls Sccb Pictured Shutdown Procedures Description Location Function Switches Behind SCC Control Panel Door Menu Tree Master Menu Screen WALK-IN Display modules only Customer Alarm Definitions SCC only Load Transfer Procedures SCC onlyBattery Time modules only Output Metering Displays Monitor/Mimic Display ScreenInput Metering Displays Item 5 Module Status Messages Status/Alarm Message AreasItem 7 Alarm Messages Item 6 System Status Messages Module Monitor/Mimic Display Screen Alarm Messages Item 5 Alarm Messages MOD 1 on Line MOD 2 on Line MOD 3 on Line UPS Ratings UPS Input PWR UPS Ratings UPS Input PWR Bypass Input Load Bypass Input C-A Walk-In Display Screen Walk-In Display Screen During Start-Up Status Reports Screens Status Reports Screen Present Status Select Exit Event History Event History MODULE-0 History Status History Status Report Screens SCC Module Battery Cycle Monitor Module Only System Status Battery Cycle Monitoring Summary Screen System Configuration Screens System Configuration Date Date Screen Time Time Screen Auto Dial Dial Modem Baud Rate Modem Baud Rate Maximum Auto-Retransfer Attempts Retransfer Attempts Remote Monitor Alarm Limit Settings Screen Alarm Settings Product Load Transfer Procedures Screen Refer to 3.3.2 Load Transfer Procedures for more details Start-Up Procedures Screen Refer to 3.3.1 Start-Up Procedure for more details Module Start- Up Procedures Screen Shutdown Procedures Screen Shutdown Procedures Module Shutdown Procedures Screen Battery Time Screen Module Only VDC Battery Time Screen Example 45 Minute Discharge Range of Values for Calculated Battery Times Aining Rem Tim Calculated La p s e d T im e M in u te s Meter Calibration Screen UP Cursor UP Down Cursor Down Select Choose Battery Equalize Screen Battery Equalize Recharging Alarm and Status Messages Module Status Messages 3 Modules Connected System Status Messages Load Block Messages Abbreviations Used in Alarm Messages OF/UF Power DC Ground FaultBattery CB Open Battery Bypass Phase Manual ResetStatic Switch Control Power System Configuration Screens or the watchdog timer has AlarmIndications and Other Alarms That Activate Summary Alarms Reverse Power Timeout TemperatureOver-Temperature System Configuration Screens Load On UPS Alarm Message Special Functions Auto-Dial Communication InterfacesWorldwide Reporting Requesting Information Site Reporting SiteScan or Snmp Local Reporting to a TerminalLocal Reporting to a Monitor Remote Monitor Panel Separate / Simultaneous Outputs Load On Bypass Scct OK To Transfer Load on Bypass UPS Available Load on UPS Bypass Available Momentary Overloads Refer to 3.4 Automatic Operations Input Power Failure Load On Battery Input Power Fail Load on Battery One Module Off-Line One Module Off-Line Load on UPS Off Battery Load on UPS Battery Not Available Refer to 3.3.3 Shutdown Procedures Emergency Modules Off Emergency Power Off Emergency Power Off Refer to 3.2.10 Maintenance Bypass System Shutdown Load on Maintenance Bypass Two Breakers Load on Maintenance Bypass Three Breakers Manual Procedures Refer to 3.4 Automatic Operations for more details Start-Up Procedure SCC Start-Up B2. Set the Static Switch Disconnects OFF open SCC Start-Up Procedures Screen UPS Module Start-Up Module Start-Up Procedures Screen Product Load Transfer Procedures If the load is on Maintenance Bypass Maintenance Bypass Load TransfersMaintenance Bypass System Bypass Shutdown Procedures System Shutdown Procedure UPS bypass line is still energized 100 Module Shutdown Procedure Remote Emergency Power Off Repo Local Emergency Modules Off Lemo Automatic Operations Overloads Without Transfer Automatic Transfers to Bypass Automatic Retransfers to UPS Automatic Module Off-Line Automatic Emergency Modules Off Maintenance DIS Product Professional Start-Up Liebert Global ServicesMaintenance Agreements The Signature Program Training Air Filters Routine MaintenanceRecord Log Battery Maintenance Battery Safety Precautions DIS Product 112 DIS Product Rack-Mounted Batteries Matching Battery Cabinets OptionalPower Batteries Torque Requirements Torque Specifications Unless Otherwise Labeled Detection of Trouble Recommended Test Equipment Reporting a ProblemCorrective Actions Rating Environmental Conditions Adjustments Battery Operation Electrical Specifications Voltage Transient Recovery Time Voltage Adjustment RangePhase Balancing Voltage Harmonic Content Series 600T UPS