Toshiba GRL100-701B Instruction Manual page 92

is switched onto a system that has previously been loaded to 90% of its capacity.
Thermal Curves (Cold Curve - no
prior load)
1000
100
10
1
0.1
0.01
1
Overload Current (Multiple of I
Scheme Logic
Figure 2.8.2 shows the scheme logic of the thermal overload protection.
The thermal overload element THM has independent thresholds for alarm and trip, and outputs
alarm signal THM ALARM and trip signal THM TRIP. The alarming threshold level is set as a
percentage of the tripping threshold.
The alarming and tripping can be disabled by the scheme switches [THMAL] and [THMT]
respectively or binary input signals THMA BLOCK and THM BLOCK.
367
A
THM
363
T
[THMAL]
+
"ON"
[THMT]
+
"ON"
THMA_BLOCK
1593
THM_BLOCK
1594
Figure 2.8.2
Thermal Curves (Hot Curve - 90%
1000
100
10
1
τ
100
50
0.1
20
10
0.01
5
2
1
0.001
10
1
)
AOL
Overload Current (Multiple of I
Figure 2.8.1 Thermal Curves
&
&
1
1
Thermal Overload Protection Scheme Logic
 91 
prior load)
100
10
)
AOL
416
THM ALARM
&
417
THM TRIP
&
6 F 2 S 0 8 5 0
τ
50
20
10
5
2
1