L2275
Emax UL
50/132
Doc. N°
Mod.
RH0109002
Apparatus
Scale
Page N°
Signaling
Description
Yellow magnetic flag “
θ
”
Trip of protection “T” for overtemperature (second threshold: T=85°);
Yellow magnetic flag “L”
Trip of protection “L”;
Yellow magnetic flag “S”
Trip of protection “S”;
Yellow magnetic flag “I”
Trip of protection “I” or “Iinst”
Yellow magnetic flag “G”
Trip of protection “G”;
13.15.3.2 Electrical signals
Electrical signals (see par. on Inputs/Outputs)
Signaling
Description
Contact K51/p1
The signaling to which it is connected (see Table par.13.11.1) is active;
Contact K51/Y01
Any one of protections “ L, S, I, G and
θ
“ has tripped;
Contact K51/uP
Microprocessor with temporary or permanent fault. (closes with delay of 1...2 s). Only operational with Auxiliary
power supply.
By pressing the “Reset” pushbutton, it is possible to reset the state of the magnetic flags and of the contacts.
This pushbutton is effective when there is self-supply or an auxiliary power supply.
Otherwise the energy accumulated by a special ‘buffer’’ RESET capacitor is used, which is charged in 12s under self-supply running. This
guarantees, in the case of no self-supply and auxiliary power supply, at least one RESET operation for 6 hours at 25°C.
In the case where the ‘buffer’ capacitor is also discharged, it can be used to RESET the PR120/B supplementary power supply unit.
In this situation, power circuit breaker closing is always possible, both by means of Closing Coils (BC) and by means of a mechanical pushbutton.
Operation of the trip unit is ensured immediately after closing, whereas signal resetting can only be carried out after 12 seconds.
13.16
Troubleshooting
The following table gathers together a series of typical service situations, which are useful to understand and solve hypothetical faults or
malfunctions.
N.B.:
1. Before consulting the following table, check any signaling of error messages on the first line of the display for a few seconds.
2. FN indicates normal operation of the PR112.
3. In the case when the suggestions proposed do not lead to a solution of the problem, please contact the ABB SACE Assistance service.
N°
Situation
Possible causes
Suggestions
1
It is not possible to reset the magnetic
The buffer capacitor is discharged
FN, connect the Vaux, the PR010/T or the
signals
PR120/B, to reset
2
It is not possible to carry out the
1. The busbar current is > 0.
1. FN
trip test
2. The SA is not connected
2. Connect the SA
3
Trip times lower than those expected
1. Threshold too low
1. Correct threshold
2. Curve too low
2. Correct curve
3. Thermal memory inserted
3. Exclude if not necessary
4. Incorrect Neutral Selection
4. Correct Neutral Selection
5. The SdZ is inserted
5. Exclude if not necessary
4
Trip times higher than those expected
1. Threshold too high
1. Correct threshold
2. Curve too high
2. Correct curve
3. Curve I
2
t inserted
3. Exclude if not necessary
4. Incorrect Neutral Selection
4. Correct Neutral Selection
5
Rapid trip, with I3=Off
Iinst trip
FN with short circuit with high I
6
I of ground high, but there is no trip
1. Incorrect selection of the sensor
1. Set int. or ext. sensor
2. Function G prevented with I>4 In
2. FN
7
Display off
1. Vaux missing and the I of busbar
1. FN, see 13.3.1
2. Temperature out of rangeis less
than the minimum value
2. FN, see 13.7.6
8
The display is not rear-lit
Vaux missing
FN
9
Reading of I incorrect
Incorrect setting of In
Change parameters, see 13.15.2.1