Residual

curr

ent

devices

Low Voltage Products & Systems

Difference between RCD and MCB

Miniature Circuit Breaker (MCB)

Residual Current Device (RCD)

RCD’s are sensitive to

a 30-300mA. RCD’s are mechanical devices that contain a CT and a

solenoid.

Ground Fault Interrupter (GFI)

Application manual

Example of current leakage to ground

L1

N

L1

N

Abrasion in wire;

small (mA)

leakage to ground

Current ow

Current ow

X

Neutral (N) return path is not

equal to the current in the hot

(L1) path (leakage to ground);

there is an imbalance

between the

L1 and N.