Communication solutions for power utilities
UNIVERSAL TELEPROTECTION TPU-1
INSTALLATION AND COMMISSIONING MANUAL Web version TPU-1R - Rev. 5.9 (May 2018)
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4.1
POWER SUPPLY
As seen from the rear, the position most to the right corresponds to the main power-supply
module type ATPU. If redundancy is used, the secondary power supply is located next to
the main power-supply module.
Figure 12 shows a front view of the ATPU power-supply module. As can be seen, the
power-supply module has two terminal blocks on the front plate. One is associated with the
power supply and the other to the power-supply alarm relay.
In normal operation conditions the alarm relay is energized, that is to say, the N.O. and C
contacts are short-circuited. Should a failure occur in the power supply, not only does the
LED POWER FAIL on the front plate light up but the N.C. and C contacts of the alarm
relay are also short-circuited.
Figure 12 ATPU power-supply module
