GE DS3820EPSA

Parameters

Advantages & Features

• Universal Input – The GE DS3820EPSA accepts both AC (85–264V) and DC (100–300V) without configuration changes, simplifying global installation and eliminating input selection errors.

• Built-in Redundancy – Two GE DS3820EPSA modules can be paralleled using built-in ORing diodes. If one fails, the other automatically carries the full load with zero voltage drop (<0.3V differential).

• Comprehensive Diagnostics – The front-panel LCD displays real-time parameters, while alarm relays provide remote fault notification. The GE DS3820EPSA also reports status to the Mark VIe controller via the backplane for system-level monitoring.

• High Efficiency – >88% efficiency reduces heat generation, allowing operation up to 70°C with minimal derating, critical for turbine cabinet installations with limited cooling.

• Hot-Swappable – The GE DS3820EPSA can be replaced without powering down the rack, supporting online maintenance in critical power generation applications.

• Hold-up Time – 20ms hold-up ensures the GE DS3820EPSA rides through brief power dips without causing I/O module resets.

Application Cases

• Gas Turbine Control Cabinet – A single GE DS3820EPSA powers the entire Mark VIe rack (CPU, I/O modules, communication cards) in a 7FA gas turbine installation, with a redundant second module providing N+1 backup.

• Steam Turbine Retrofit – Replaces legacy Mark IV power supplies (multiple 125VDC bricks) with a single GE DS3820EPSA, reducing cabinet size and improving reliability.

• Offshore Platform – Two GE DS3820EPSA modules operate in redundant parallel with separate input feeds (UPS and emergency diesel), ensuring continuous power during transfer switching.

• Combined-Cycle Plant – Powers Mark VIe I/O racks distributed across HRSG and turbine areas, with alarm relays connected to DCS for remote status monitoring.

Competitor Comparison

The GE DS3820EPSA offers wider input range, more outputs (24V + 5V + aux 24V), higher efficiency, and built-in LCD compared to competitors. ABB lacks hot-swap capability; Rockwell’s lower power output limits rack expansion.

Selection Suggestions

• Select the GE DS3820EPSA as the default power supply for any Mark VIe rack, regardless of input source (AC or DC). Its universal input eliminates ordering errors.

• For N+1 redundancy, install two GE DS3820EPSA modules in the same rack. Both must be powered from separate input sources for true fault tolerance.

• Calculate total rack power: sum 24V and 5V loads of all modules. The GE DS3820EPSA provides 10A at 24V and 5A at 5V — sufficient for typical 10-slot racks with 8 I/O modules.

• If rack expansion exceeds 300W, use the GE DS3820EPSA-HD variant (not this model) or distribute loads across multiple racks.

• Connect alarm relays (normally energized) to your DCS for remote fault indication. Relay contacts are rated 2A@30VDC.

• For marine/offshore installations, verify the GE DS3820EPSA has DNV GL certification (available as option).

Precautions

• Input Wiring – Use appropriate wire gauge for input current (max 4A at 115VAC, 2A at 230VAC). AC input must use 3-wire (L,N,G) with ground connected to cabinet ground bus.

• Output Loading – Do not exceed 10A on 24V output. The GE DS3820EPSA limits current at 11.5A (hiccup mode); excessive loads will cause cyclic power cycling.

• Parallel Operation – When using redundant GE DS3820EPSA modules, ensure both are powered on and stable for at least 3 seconds before loading. ORing diodes handle sharing but do not provide active current balancing — one unit may carry slightly more load.

• Thermal Derating – Above 60°C ambient, derate output power by 2.5%/°C. At 70°C, maximum output is reduced to 225W. Ensure cabinet ventilation meets the module’s airflow requirement (50 CFM recommended).

• Mounting Orientation – The GE DS3820EPSA must be mounted vertically (as in VME rack) for proper convection cooling. Horizontal mounting is not permitted.

• Battery Backup – The GE DS3820EPSA is not a battery charger. If backup batteries are required, use a separate charger module and connect batteries through external ORing diodes.

• LCD Cleaning – Use only dry cloth; solvents will damage the display coating.

• Calibration – The GE DS3820EPSA is factory-calibrated and does not require field calibration. LCD display accuracy is ±2% of reading — verify with external meter for critical measurements.

• Replacement – When replacing a failed GE DS3820EPSA in a redundant pair, insert the new module, wait 5 seconds for stabilization, then remove the old module. Do not remove the active module first.