Advanced MX-4200V, Manual

Page: 52 / 72

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5.2.3 Fire / Fault Routing Circuit Lengths
The voltage drop on each transmission circuit should be calculated to ensure that the minimum voltage at the
end of the circuit exceeds the minimum required by the relay coil at the minimum circuit output voltage.
Typically, relays will energise at 75% of their nominal drive voltage (i.e. 18V for a 24V coil)
The voltage at the end of the circuit is given by:
Minimum Coil Voltage = V
OUT(MIN)
– (I
ON
x R
CABLE
)
Minimum Output Voltage (V
OUT(MIN)
) is V
AUX(MIN)
– 0.8V = 19.7V
Maximum On Current (I
ON
) is 35mA.
Cable Resistance (R
CABLE
) is as above.
Insulation Resistance
(Core-Core and Core-
Screen)

2M Ω
5.2.4 Network Cables
For a list of recommended cables, refer to the AdNeT document 680-027.
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