300 amp dc power system

Product Information

Guardian Access 3U is a 3RU high 19” rack-mounted, integrated 300 Amp DC power system providing an output of -48VDC. These systems can accommodate up to 5 Guardian family high efficiency hot-swap rectifiers.

This 300 Amp DC power system provides a total load current of 200A with battery charge current up to 100A in addition. The rectifiers are internally fan cooled with speed control which is a function of load and temperature, keeping acoustic noise to a minimum.

The DC output circuits can provide up to 13 loads which utilize circuit breakers rated from 4A to 150A  plus  up to three 80A, 100A or 125A breakers that provide battery protection.  A programmable low voltage battery disconnect (LVBD) is available with options of 125A or 200A; while a partial load disconnect (PLD), rated at 125A and also programmable, can provide non-critical load shedding when operating on batteries.


Features and Options
  • >96% Efficiency Rectifiers
  • 300A / 14.4kW Total Capacity
  • Remote Monitoring & Control
  • Intelligent Battery Management
  • Field Replaceable Controller
  • Ethernet Comm. with SNMPv3
  • 3 LED Alarm/Status Indicators
  • Up to 10 Form-C Relay Alarms
  • Up to 13 Load Breakers
  • Up to 3 Battery Breakers
  • LCD Display/Touchpad
  • Easy Installation
System Voltage-48VDC nominal | -53.5 float (factory default setting, user adjustable)
Maximum Capacity @ 120VAC nominalLoad - 175A
Battery - 175A discharge | 75A charge (s/w controlled)
Maximum Capacity @ 230/400VAC nominalLoad - 200A
Battery - 200A discharge | 100A charge (s/w controlled)
No. Rectifier Slots5
Load Circuits13 x 13mm or 9 x 18mm (4A to 150A)
Battery Circuits3 x (80A, 100A or 125A)
Voltage (nominal)1-phase 100-120/200-240VAC (L + N + PE)
3-phase 230/400VAC (L1 L2 L3 + N + PE)
Maximum Input Current82A @ 100-120VAC | 65A @ 200-240VAC | 13A per phase @ 400/230VAC
Rectifier Power Factor>0.98 (typical)
Surge ProtectionOptional
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)1 x 125A or 200A Programmable (Optional)
Partial Load Disconnect (PLD)1 x 125A Programmable (Optional)
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)
Standard Cover19.0 (483) W x 5.2 (132) H x 16.1 (408) D
Extended Cover19.0 (483) W x 5.2 (132) H x 19.1 (454) D
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.  
STOCK MODELS (normally held in stock for immediate delivery)
MS0027G*900041 3 Rectifier Position Chassis
ACX Controller
4 alarm relays
100A Battery Breaker (x2)
Load Breakers (18mm): 63A/63A/32A/32A/20A/20A /10A /10A
3m Temp. Sensor Cable (x1)
3m Symmetry Cable (x2)
Standard Cover Kit

[Rectifiers & Dummy Modules must be ordered separately.]
5 Rectifier Position Chassis
ACX Controller
4 alarm relays
100A Battery Breaker (x2)
Load Breakers (18mm): 63A/63A/32A/32A/20A/20A /10A /10A
3m Temp. Sensor Cable (x1)
3m Symmetry Cable (x2)
Standard Cover Kit

[Rectifiers & Dummy Modules must be ordered separately.]
For complete details and order codes for rectifiers and accessories see the datasheet.