Eaton IQ 200, Инструкция по установке, эксплуатации и обслуживанию

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TD 17558
Page 23
Effective 3/98
(
±
Wh)
; or
leading or lagging reactive (
±
varh)
. The procedure for specifying the
energy per pulse is described in section 4.10.9 .
Each pulse that arrives at the pulse counter indicates that the specified energy has
been consumed by the monitored system. The frequency and spacing of these
pulses represent the energy consumption pattern of the monitored system.
Because the energy represented corresponds to the energy at the secondary
winding of the PTs and CTs, the CT and PT ratios must be taken into account when
specifying the
energy per pulse value. An example of how to specify the energy per
pulse value is given below.
Example:
System Configuration
CT = 1400:5
PT = 2:1
Desired value to monitor
Watt-hours
System parameters
Assume
the IQ 200 is monitoring a constant system power of 16,800 Watts.
Step 1 : Calculate the CT and PT ratios
CT ratio = 1400/5 = 280
PT ratio = 2/1=2
Step 2
: Calculate the power at the secondary of the CTs and PTs
power at secondaries = 16,800 Watts / (CT ratio x PT ratio)
power at secondaries = 16,800 Watts / (280 x 2)
power at secondaries = 16,800 Watts / 560
power at secondaries = 30 Watts (or 30 Watt-hours in 1 hour)
Step 3 : Specify the energy per pulse as desired
Specify secondary energy per pulse = 1 Watt-hour per pulse;
then, each pulse represents system energy of:
(1400/5) x (2/1) x 1; or 560 Watt-hours per pulse
or
Specify secondary energy per pulse = 7 Watt-hours per pulse;
then, each pulse represents system energy of:
(1400/5) x (2/1) x 7; or 3,920 Watt-hours per pulse