6750 amp dc power system

Product Information

Guardian Central is a multi-cabinet integrated 1350 to 6750 amp DC power system providing an output of -48VDC. Each 2.1m high cabinet can accommodate up to 24 Guardian family high efficiency hot-swap rectifiers along with AC input and DC output distribution. A load current of 1100A plus 250A for battery charge is available from each cabinet with a maximum system capacity of 5500A when 5 cabinets are connected in parallel. The rectifiers are internally fan cooled with speed control which is a function of load and temperature, keeping acoustic noise to a minimum.

Each cabinet can provide up to 4 bulk DC outputs at 384A or 600A via fuses or MCBs. Additionally a maximum of 72 lower current distributed outputs are available via MCBs rates from 6A to 63A. Batteries are protected by a combination of an 1100A low voltage battery disconnect (LVBD) and fuses or alternatively using MCBs. In both cases a 1500A shunt is used to measure battery current both while charging and discharging.

Matching load distribution cabinets allow for extra DC output distribution with the same options as for the main system cabinets.


Features and Options
  • High density (31.3 W/in³) rectifiers with configurable up to 72kW per cabinet; Maximum 361kW when paralleled
  • State-of-the-art system controller with self-guided operation, SNMP and web compatible
  • Sophisticated management features extend the battery life and monitor critical site equipment such as HVAC and generators
  • Design caters for poor grid quality supply
  • Deployable and upgradable for use in Hybrid Power applications
System Voltage-48VDC nominal | -53.5 float (factory default setting, user adjustable)
Maximum Capacity Load - 1100A
Battery - 1100A discharge | 250A charge (s/w controlled)
No. Rectifier Slots 4 to 24 (see datasheet for configuration guide)

Load Circuits
(also available from distribution cabinet)

MCBs: 24 x 2 to 63A; 16 x 63 to 125A; 12 x 2 to 63A + 8 x 63 to 125A; 2 or 4 x 384A; 2 x 600A
Fuses: 8 x NH00; 4 x NH2; 3 x NH3; 6 x NH3
Battery CircuitsMCBs: 1 x 1500A; 2 x 600A; 4 x 384A; 2 x 384A
Fuses: 3 x NH3; 6 x NH3
Voltage (nominal)2 x 3-phase 230/400VAC (L1 L2 L3 + N + PE)
Maximum Input Current 2 x 72A per phase @ 400/230VAC
Rectifier Power Factor>0.98 (typical)
Surge ProtectionOptional
Distribution / Current Protection Optional PDU with MCBs: up to 24 x 32A
MONITORING & CONTROL (ACX Advanced Controller)
Alarm Relays4 standard, option for 10
Local Interface 4 x 20 LCD, 4-key menu, USB / RS232, microSD card slot (4GB max,) for data logging
Remote InterfaceEthernet / Modem using PowCom™ software package
Ethernet port allows monitoring and control over a TCP/IP network.
Web browser support + SNMPv3
LED IndicationsGreen - System ON; Yellow - Message(s); Red LED - Alarm(s)
External Digital I/O 2 x Inputs, 2 x Outputs (TTL Level)
Symmetry Inputs6 or 12 (can be redefined as analog inputs up to 100VDC)
Low Voltage Battery Disconnect (LVBD) Main Cabinet: 1 x 1100A Programmable | Extension Cabinet: 1 x 1100A Programmable
Temperature Compensated ChargingProgrammable
EMCEN 300 386 ; EN61000-6-3 (Emission) ; EN61000-6-2 (Immunity)
SafetyIEC60950-1:2005 2 Ed. +A1:2009
Operating Temperature-40ºC to +55ºC
Storage Temperature-40ºC to +85ºC
DIMENSIONS, ins. (mm)
Main Cabinet 82.7 (2100) H x 23.6 (600) W x 23.6 (600) W
Extension Cabinet 82.7 (2100) H x 23.6 (600) W x 23.6 (600) W
Battery Disconnection Provides voltage controlled disconnection of batteries.
Boost Charging Manual time controlled or automatic boost charging with adjustable time and voltage levels.
Battery Tests Automatic or manual testing of batteries up to six times per year with a 10 test memory. Variables include test duration and end voltage.
Battery discontinuance test to ensure battery connection.
Enhanced Battery Monitoring Monthly logging of essential battery parameters including temperature, temperature hours, current, charging voltage and symmetry voltage, Data logged for 5 years.
Site Logs System tools developed to assist site management. Daily peak load and statistic logs available.
Symmetry Measurement Optional tool that measures batteries for early detection of thermal runaway.
Temperature Compensation Charging

Allows continuous adjustment of output voltage according to battery temperature.
Features include adjustable compensation factor and separate thresholds for high temperature alarms.

Load Shedding (PLD) Optional feature that allows voltage or time controlled disconnection of non-essential load.