Basler BE1-49, Instruction Manual

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4-2 BE1-49 Installation
CAUTION
If a relay built before mid 1996 is used with grounded RTDs, the relay must use
a Type E power supply. Refer to the power supply discussion in Section 3,
Functional Description
.
D1427-01.VSD
12-04-01
Figure 4-1. S1 Case, Outline Dimensions, Front View
To prevent an inductive overload of the relay contacts, it is necessary to break the trip circuit externally
through the 52a contacts. (see Figure 4-11).
Terminals 3 and 4 are external relay power supply voltage inputs and are not polarity sensitive. Terminals 6
and 8 are the constant current supply to the RTD.
Terminals 7 and 9 are the voltage sensing inputs to the relay. To achieve the rated temperature accuracy for
the relay, a wire should be connected from each of terminals 6, 7, 8, and 9 to the RTD. Each of the four wires
should have less than 20 ohms of resistance. If less than rated temperature accuracy is acceptable, terminals
6 and 7 may be jumpered together and terminals 8 and 9 jumpered together.
The relay circuitry is connected to the case terminals by removable connecting plugs (1 for 10 terminal cases,
2 for 20 terminal cases). Removal of the connecting plug(s) opens the NO trip contact circuit and shorts the
NC trip contact circuit before opening the power and sensing circuits.
ADJUSTMENTS
The relay has been calibrated at the factory and it is strongly recommended that the calibration adjustments
not be disturbed. If, however, relay pickup accuracy is suspect for any reason, remove the relay from service
and check the temperature settings using the procedures given in Section 5 of this manual.