Multilin SR469, Инструкция по эксплуатации

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2. INSTALLATION ELECTRICAL
2-11
2.2.6 VOLTAGE INPUTS
The SR469 has three channels for AC voltage inputs, each with an
isolating transformer. There are no internal fuses or ground
connections on the voltage inputs. The maximum VT ratio is
150.00:1. The two VT connections are open delta (see Figure 2-12)
or wye (see Figure 2-19). The voltage channels are connected in
wye internally, which means that the jumper shown on the
delta-source connection of Figure 2-13, between the phase B input
and the SR469 neutral terminal, must be installed for open delta
VTs.
Polarity of the VTs is critical for correct power measurement and
voltage phase reversal operation.
Typically a 1A fuse is used to protect the inputs.
Figure 2-19 WYE VOLTAGE TRANSFORMER CONNECTION
2.2.7 DIGITAL INPUTS
There are 9 digital inputs that are designed for dry contact connections only. Two of the digital inputs, Access and Test have their own
common terminal, the balance of the digital inputs share one common terminal (see Figure 2-12).
In addition, the +24Vdc switch supply is brought out for control power of an inductive or capacitive proximity probe. The NPN transistor
output could be taken to one of the assignable digital inputs configured as a counter or tachometer. Refer to the Specifications section of
this manual for maximum current draw from the +24Vdc switch supply.
CAUTION: DO NOT INJECT VOLTAGES TO DIGITAL INPUTS. DRY CONTACT CONNECTIONS ONLY.