Schweitzer Engineering Laboratories SEL-734 - Figure 4.3 Response of Thermal, Rolling, and Block Demand Meters to a Step Input (Setting DMTC=15 Minutes)

4.6
SEL-734 Meter Instruction Manual Date Code 20090730
Metering
Demand Metering
Comparison of
Thermal, Rolling, and
Block Demand Meters
The example in Figure 4.3 shows the response of thermal, rolling, and block
demand meters to a 1.0 per unit step energy input.
Figure 4.3 Response of Thermal, Rolling, and Block Demand Meters to a
Step Input (Setting DMTC=15 Minutes)
0
5
10
15
Time
(Minutes)
1.0
0.5
0
Instantaneous Current (per unit)
Step
Current
Input
0
5
10
15
Time
(Minutes)
1.0
0.9
0.5
0
Thermal Demand Current (per unit)
Thermal
Demand
Meter
Response
(EDEM=THM)
DMTC=15 minutes
0
5
10
15
Time
(Minutes)
1.0
0
0.67
0.33
Rolling Demand Current (per unit)
Rolling
Demand
Meter
Response
(EDEM=ROL)
DMTC=15 minutes
0
5
10
15
Time
(Minutes)
1.0
0
Block
Demand
Meter
Response
(EDEM=BLOK)
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