ISOLGUARD HIG93, HIG93/L, HIG94
V5.8/23
HAKEL spol. s r.o. Hradec Králové
www.hakel.com
Page 11 / 15
6. Insulation resistance fault evaluation
Evaluation of the
FAULT1, FAULT2
according to set
t
ON
and
R
hyst
parameters values is shown in the following figure.
In this example, the set non-zero value for
t
ON
and hysteresis
R
hyst
is shown without setting the
FAULT
memory parameter.
When the insulation resistance value of the monitored power supply system decreases below
R
crit1
or
R
crit2
, the countdown of
the time
t
ON
starts. The remaining time is displayed. Once the time
t
ON
is expired, the fault is signalized and the
FAULT1,
FAULT2
indicator lamp on the device lights up. Particular signalling relay release is cancelled and its contacts are set to the
rest position. The
FAULT1,
FAULT2
is only terminated when the insulation resistance increases above the value
R
crit1
+
R
hyst
or
R
crit2
+
R
hyst
. Signalling relay is released and
FAULT1, FAULT
2 signalling is terminated.
The following left figure shows fault evaluation when insulation monitoring device is set with zero value
t
ON
. The following right
figure shows example for setting of insulation monitoring device with the hysteresis zero value
R
hyst
.
v
Picture 5: Insulation resistance fault evaluation
Picture 6: Insulation status fault evaluation with time
t
ON
or hysteresis zero value
Time
Time
No FAULT1
FAULT1
No FAULT2
FAULT2
Time
0
Risol
Rcrit1 Rhyst=0
0
tON
Rcrit2 Rhyst=0
tON
0
Time
Time
No FAULT1
No FAULT2
Time
0
Risol
FAULT1
Rcrit1
Rhyst
0
tON=0
FAULT2
Rcrit2
Rhyst
tON=0
0
Time
Time
No FAULT1
Signalling rellay 1 is released
Signalling rellay 1 is not released
Signalling rellay 1 is released
No FAULT2
Time
0
Risol
FAULT1
Rcrit1
Rhyst
0
tON
FAULT2
Rcrit2
Rhyst
tON
0
