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- Ground Fault Monitoring for Grounded Systems

LINETRAXX® RCMA420
- Ground-fault monitor for grounded and high-resistance grounded AC/DC systems
- Modular installation using a single external current transformer
- Works with AC/DC power conversion equipment including variable frequency drives
- Digital display with real-time readings
- Configurable Form-C (SPDT) relay contacts
The RCMA420 monitors for ground-fault current in solidly-grounded and high-resistance-grounded AC/DC (single-phase or three-phase) systems. The RCMA420 is also compatible with systems that contain power conversion equipment, such as variable frequency drives and inverters.
The pickup value is adjustable from 10 mA to 500 mA (for a higher pickup value, refer to RCMA423 series). A separately configurable pre-warning alarm is also available. Three separately adjustable time delays are included - a pickup delay, startup delay, and delay on reset.
The RCMA420 provides an accurate, RMS value. Measurements are displayed in real-time via the device's on-board digital display. All device are configured using the display and push buttons. Two Form-C (SPDT) relay outputs are separately configurable to trigger on pre-warning or main alarms.
A single current transformer connects to the RCMA420 for measuring ground-fault current. A wide range of sizes are available.
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- Ground-fault monitoring for solidly-grounded and high-resistance-grounded AC/DC systems
- Meets or exceeds code requirements for ground-fault detection on grounded AC/DC systems, where applicable
- Works on systems with power conversion equipment, including variable frequency drives and inverters
- RMS measurement values
- Digital display showing measured ground-fault current in real-time
- Adjustable pickup value from 10 to 500 mA
- Connects to a single current transformer, available in a wide range of sizes
- On-board test and reset buttons with connections for external activation
- Adjustable time delays (pickup, startup, on reset)
- Latching or non-latching operation
- Two Form-C (SPDT) alarm outputs, operating normally energized (failsafe) or de-energized (non-failsafe)
- Ground-fault monitoring on grounded and high-resistance grounded AC/DC systems
- General power distribution
- Motors and motor control centers
- Generators, portable and fixed
- Control systems
- Heat trace systems, per NEC 427.22 and CEC 62-116
- Battery backup systems
- Grounded solar arrays, per NEC 690.41(B) (2017 edition), NEC 690.5 (2014 edition), and CEC 64-064(4)
- Energy storage systems
Mandatory accessories for LINETRAXX® RCMA420
Part No. | Opening | Shape and Type | Ordering No. |
---|---|---|---|
CTUB101-CTBC20 | 0.78" (20mm) | circular, solid | B78120010 |
CTUB101-CTBC20P | 0.78" (20mm) | circular, solid | B78120020 |
CTUB101-CTBC35 | 1.35" (35mm) | circular, solid | B78120012 |
CTUB101-CTBC35P | 1.35" (35mm) | circular, solid | B78120022 |
CTUB101-CTBC60 | 2.4" (60mm) | circular, solid | B78120014 |
CTUB101-CTBC60P | 2.4" (60mm) | circular, solid | B78120024 |
Optional accessories for LINETRAXX® RCMA420
Part No. | Length | Ordering No. |
---|---|---|
CTX-100 | 3' (1m) | B98110080 |
CTX-250 | 8' (2.5m) | B98110081 |
CTX-500 | 16' (5m) | B98110082 |
CTX-1000 | 32' (10m) | B98110083 |
Variants of LINETRAXX® RCMA420
Part No. | Supply Voltage | Ordering No. |
---|---|---|
RCMA420-D-1 | 16-72 VAC (42-460 Hz), 9.6-94 VDC | B94043001 |
RCMA420-D-2 | 70-300 VAC (42-460 Hz), 70-300 VDC | B94043002 |
Downloads for LINETRAXX® RCMA420
Category | Product | Language | Size | Download |
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