Description
Key Technical Specifications
- Product Model: 8920-PS-DC
- Manufacturer: GE (General Electric)
- Product Type: Intrinsic Safety (IS) DC Power Supply
- Input Voltage Range: 18.5 VDC to 36 VDC
- Output Voltage: 12 VDC
- Output Current: 5A
- Dimensions: 84mm (W) x 110mm (H) x 160mm (D)
- Weight: 1.29 kg
- Protection Features: Overload and short-circuit protection
- Operating Temperature: +5°C to +55°C
- Installation: Control Room / DIN Rail Mount
Product Introduction
Sourcing replacement power supplies for legacy Intrinsic Safety (IS) systems is a critical headache when dealing with hazardous area classifications. The GE 8920-PS-DC is engineered specifically to eliminate this friction. Serving as the dedicated power backbone for the GE IS series, this module ensures that field devices in explosive atmospheres receive stable, strictly regulated DC power without risking ignition.
Bottom line — it delivers safe, reliable power. Designed for harsh industrial environments, it features a wide 18.5-36VDC input range to accommodate voltage fluctuations and includes built-in overload and short-circuit protection to safeguard downstream IS modules. With a 12VDC 5A output capacity, it handles continuous duty reliably. Always verify the exact hardware revision against your existing IS rack before installation to maintain safety compliance.
QA/QC Transparency SOP
Buying surplus IS power supplies requires strict validation. Here is our testing protocol for the 8920-PS-DC:
- Intake & Origin Verification: We trace the lot and inspect the PCB for counterfeit GE silkscreens or unauthorized rework.
- Live Functional Testing: Mounted on a dedicated test rack to verify the 18.5-36VDC input range and confirm a stable 12VDC 5A output under load.
- Electrical Parameter Tests: Fluke multimeter checks on input/output terminals to ensure protection circuits (overload/short) are fully functional.
- Firmware/Config Verification: Internal regulation parameters are logged to ensure no degraded components.
- Final QC & Anti-Static Packaging: Sealed in an ESD-safe bag with heavy bubble wrap to protect the sensitive power regulation components during transit.
Field Engineer Gotchas
- Input Voltage Out of Range: This module requires a minimum of 18.5VDC. If your 24VDC power supply is sagging due to aging or heavy load, the 8920-PS-DC will shut down or output erratic voltages. Measure with a multimeter before condemning the module.
- Short-Circuit Protection Latch: If a downstream IS module shorts out, this power supply will trip its protection. Simply replacing the PSU without finding the shorted field device will just blow the new supply. Always check the field wiring first.
- Ground Loop Noise: IS power supplies are highly sensitive to grounding. If your 12VDC output has excessive ripple, do not blame the module immediately. Check if the IS ground is properly isolated from the main cabinet ground.
- War Story: I once spent hours troubleshooting a GE IS power supply that kept tripping offline. The module tested perfectly on the bench. Turned out a moisture-damaged proximity sensor in the field was intermittently shorting to ground. Always verify the field wiring and isolation barriers before swapping expensive IS power supplies!
GE-8920-PS-DC
Application Scenarios
- Oil & Gas Refineries: Requires strict intrinsic safety compliance to power field transmitters in Class I, Div 1 hazardous zones.
- Chemical Processing Plants: Demands reliable 12VDC 5A output to maintain continuous level and pressure monitoring in explosive atmospheres.
- Offshore Platforms: Needs wide 18.5-36VDC input tolerance to handle voltage drops across long DC power distribution cables.
- Case Study: A chemical plant experienced frequent IS power supply trips during heavy rain. Maintenance suspected a failing 8920-PS-DC module. Our analysis revealed the module was functioning perfectly, but a degraded cable gland on a field junction box was allowing moisture ingress, causing an intermittent ground fault. Replacing the junction box and verifying the PSU restored stable power, avoiding a costly hazardous area re-certification.
FAQ
Q: Can I use a standard 24VDC power supply instead of this IS module?
Absolutely not. The 8920-PS-DC is specifically designed with intrinsic safety barriers and energy-limiting circuits. Using a standard power supply in an IS zone violates safety regulations and risks catastrophic ignition.
Q: Will this drop into an existing GE IS chassis?
Yes, the 8920-PS-DC is designed for standard GE IS series racks. However, ensure your backplane power rating can handle the module’s draw.
Q: Does it support hot-swapping?
IS power supplies generally do not support hot-swapping in hazardous areas. Always obtain a hot work permit and follow site safety protocols before replacing power modules in classified zones.
Q: What if my old module has a different suffix?
GE updates these modules regularly. An 8920-PS-DC might supersede an older revision, but you must verify the safety certification and output specs match your system’s IS design. Do not assume plug-and-play across different safety generations.
Q: Do you provide IS safety certificates with surplus stock?
We provide functional verification and testing, but we cannot provide original OEM safety certification documents for discontinued surplus parts. We guarantee it passes live functional testing before shipment.
Q: How much current does this module supply?
The 8920-PS-DC provides a continuous 12VDC at 5A. Ensure your downstream IS modules do not exceed this total current draw.
