Overview
The General Electric GE AB-40 AC ammeter (part 50-103131-LSSC1) is a precision analog panel meter designed for industrial electrical applications requiring reliable current measurement. Built with robust mechanics and calibrated for accuracy, this AC ammeter is commonly found in power distribution systems, motor control centers, and electrical metering installations across industrial and utility settings. The meter operates at 40-70 Hz and provides straightforward dial-based current indication without external power.
Key Features
- 0-400A full-scale measurement range with 5A rated coil
- 80:1 current transformer (CT) ratio for high-amperage circuit monitoring
- 40-70 Hz frequency rating for standard industrial AC networks
- Compact round-dial design fits standard 4.5″ panel cutout
- No external power required—passive meter operation
- Factory calibrated for repeatable accuracy in field service
Technical Specifications
- Manufacturer: General Electric
- Model/Series: AB-40
- Part Number: 50-103131-LSSC1
- Measurement Type: AC Current (Ammeter)
- Full-Scale Range: 0-400A (primary circuit)
- Coil Rating: 5A
- CT Ratio: 80:1
- Operating Frequency: 40-70 Hz
- Mounting: Panel-mount (round dial, 4.5″ typical cutout)
- External Power: None required
- Construction: Analog meter—mechanical movement, dial readout
- Typical Dimensions: 4.5″ × 4.5″ face, ~2 lb weight
Typical Applications
- Industrial distribution panel current monitoring
- Motor control center metering and troubleshooting
- Utility substation and switchgear current indication
- Process equipment load monitoring
- Maintenance and field verification of current flow
- Legacy control system retrofits and replacements
Compatibility & Replacements
Compatible With
- Standard 4.5″ round-dial industrial panel cutouts
- 80:1 current transformer secondaries rated for 5A
- AC power distribution systems rated 40-70 Hz
- Direct current measurement from CT secondary circuit—no electronics or signal modules required
Replaces / Drop-In Replacement For
- Other GE AB-40 ammeters with matching 0-400A range and 80:1 CT ratio
- Equivalent third-party analog AC ammeters with identical CT ratio and frequency rating
- Verify dial range and CT ratio before substitution to ensure circuit compatibility
Works With
- Current transformer (CT) installations with 5A secondary rating
- Industrial AC networks (50 Hz, 60 Hz, or 40-70 Hz variable-speed systems)
- Direct measurement circuits—no software, PLC, or signal conditioning required
- Panel integration with existing General Electric switchgear and motor controls
