Metering
745
Transformer Management Relay
Commission
ing
http://www.GEindustrial.com/multilin
7–10
GE Multilin
3. Compare the displayed value of temperature against known temperature at the
location of the sensor. Use a thermometer or other means of obtaining actual
temperature.
An alternative approach is to perform a more detailed calibration per the procedure
outlined below.
b) Detailed Calibration of RTD Input
1. Alter the following setpoints. Set
S2 SYSTEM SETUP
!"
AMBIENT TEMP
!
AMBIENT
TEMPERATURE SENSING
to “Enabled” and set
S2 SYSTEM SETUP
!"
AMBIENT TEMP
!"
AMBIENT RTD TYPE
to the desired type.
2. The measured values should be ±2°C or ±4°F. Alter the resistance applied to
the RTD input (note the 3-input connection must be used for the measurements
to be valid) as per the
typical
table below to simulate RTDs and verify accuracy
of the measured values. View the measured values in
A2 METERING
!"
AMBIENT
TEMP
!
AMBIENT TEMPERATURE
.
Refer to RTD tables included in this manual for calibration of resistance versus
temperature.
c) Ambient Temperature by Monthly Averages
1. If the ambient temperature is entered as 12 monthly averages, program the
value for the month during which the relay is being commissioned.
2. Examine the
A2 METERING
!"
AMBIENT TEMP
!
AMBIENT TEMPERATURE
actual value
to verify the programmed temperature.
3. Verify that values entered for other months do not affect the value for the
present month.
Table 7–1: Measured RTD Temperature
RTD Type
100
Ω
Platinum
Resistance
Expected RTD
Reading
Measured RTD
Temperature
____°C ____°F
(select one)
°C
°F
100
Ω
Platinum
80.31
–50
–58
100.00
0
32
119.39
50
122
138.50
100
212
157.32
150
302
175.84
200
392
194.08
250
482
120
Ω
Nickel
86.17
–50
–58
120.0
0
32
157.74
50
122
200.64
100
212
248.95
150
302
303.46
200
392
366.53
250
482
100
Ω
Nickel
71.81
–50
–58
100.00
0
32
131.45
50
122
167.20
100
212
207.45
150
302
252.88
200
392
305.44
250
482
Summary of Contents for Multilin 745
Page 2: ......
