VAMP VAMP 150, Operation And Configuration Instructions

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VAMP Ltd Motor protection relay
Technical Description
VAMP 150
VM150.EN005 Vamp 24h support phone : +358 (0)20 753 3264
31
T> trip
T> start
Alarm Trip
T1 A1
L
VAMP 150
Output matrix
+
+ +
M
Open
coil
Close
coil
STOP START
1
Figure 3.1-1. Application where the T> start signal prevents starting of the
motor if the starting would cause heating over the trip limit
Θ
TRIP
. The T>
start signal is active when the calculated temperature exceeds the setting
value
Θ
ALARM
. The relay A1 is configured to be “normal closed”.
Q
trip
Q
load
Q
alarm
10 %
10 min 20 min 30 min 40 min 50 min 60 min
20 %
30 %
40 %
50 %
60 %
70 %
80 %
90 %
100 %
120 %
TEMPERATURE
Q
TIME
1
2
3
4
5
10 min 20 min 30 min 40 min 50 min 60 min
TIME
1
10 min 20 min 30 min 40 min 50 min 60 min
2
3
4
5
CURRENT
(x Imax)
TIME
I
load
I
max
I
start
Q
deadband
T> start
T> trip
VAMP150ThermalModelBehaviour
Figure 3.1-2. Example of modelled motor temperatures by the thermal
overload stage when current has been cut off enough long so that the motor
has cooled down. The temperature curve 5 describes an inhibited start
attempt.