Toshiba GR-200 Series Instruction Manual page 350

Stalled motor protection
2.28.5
The stalled motor protection determines whether the motor is staying at stalled condition
during the condition, when the motor status is being start-up or running. The stalled motor
protection can issue a trip signal, when overcurrent relay (Mot-Stall-OC) operates and the
stalled motor protection receives a speed switch signal from the tachometer. The Mot-Stall
function operates when On is set for the setting [Mot-Stall-EN].
Element of motor-stall overcurrent relay (Mot-Stall-OC)
The stalled motor protection has an overcurrent element to observe motor current. This
OC element operates when the motor current is larger than the pick-up value, which
the user can set with setting [Mot-Stall-OC].
Figure 2.28-10 Relay characteristic of Mot-Stall-OC
Scheme logic
The scheme logic of the stalled motor protection is illustrated in Figure 2.28-11
8000211C23
Mot-Stall-OC
800000EBB0 Mot-Stall_SpSW
830000EBB5 Mot-Stall_BLOCK
Mot-Stall-EN
MotSt-Irreg-Op
Figure 2.28-11 Scheme logic of the stalled motor protection
A speed switch signal which is generated when motor speed is decreasing is received from the
tachometer via the binary input circuit (BI) and connected to the PLC connection point [Mot-
Stall_SpSW].
The stalled motor protection can be blocked when a signal is generated at PLC connection point
[Mot-Stall_BLOCK].
0
&
1
On
- 331 -
Setting[Mot-Stall-OC]
Motor current
8000001B70
T-Mot-Stall
t 0
0.00-300.00s
6F2T0200 (0.15)
Mot-STALL-TRIP
GRE200 (1,2)