XPERT-PRO – Operational Manual
TRINITY
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should be selected from any one of the following: Demand, Avg. Volt, Avg.
Amps, KVA, KW, KVAR, and PF.
b. The
Alarm Values (K1 Value)
which are programmable from 5 to 5000 should
be selected for which the alarm parameter has to be generated. In case of PF,
the Alarm value can be set from 60 to 100.
c. The
Time Delay
(
K1 Time
) for a selected alarm parameter should be also set
from 5 seconds to 180 seconds. In case of Demand, it will be fix 2 seconds.
Understanding Hysteresis
There is a time delay involved in switching ON and OFF the relay. Also, if there is no
hysteresis in the switching operation of the relay, there is bound to be frequent
switching of the relay near the alarm value. To avoid this, a band of 5 % is added to
the programmed value, which acts when the time to switch off the relay comes .e.g.
Say, the parameter is set to KW; the value for operating the relay is programmed to
100 and the time delay is set to 30 seconds. The relay will, thus operate when the
KW crosses 100,
and stays more than 100 for 30 seconds continuously.
The relay will now open when the KW falls below 95,
and stays that way for 30
seconds continuously.
Thus, there is a time delay involved, and also a 5% band. However, since Demand is
already an integrated parameter, there is only 2 seconds delay involved when the
alarm contact is set for Demand.
In case of PF, the hysteresis is not there. However, PF has a multiplying factor (MF)
of 100. Thus, a PF value of 0.98 is set as 98. All this is summarized below:
Sr.
No.
Alarm
parameter
Relay switches
on at
Relay switches off at
Settable Time
Delay
1.
Avg. Volts
>Set value
<95 % of set value
005 to 180 sec.
2.
Avg. Amps.
>Set value
<95 % of set value
005 to 180 sec.
3.
KVA
>Set value
<95 % of set value
005 to 180 sec.
4.
KW
>Set value
<95 % of set value
005 to 180 sec.
5.
KVAR
>Set value
<95 % of set value
005 to 180 sec.
6.
Demands
>Set value
<95 % of set value
2 sec.(fixed)
7.
PF
<Set value
>Set value
005 to 180 sec.
To retrieve the K1 On, K1 Value and K1 Time, precede the following instructions.
1. In Run Mode, press
key for about five seconds and then the unit displays
the first programmable parameter, DEMAND ON. Press
keys several
times to retrieve the programmable parameter, K1 ON such as shown below.