Lochinvar Armor 101 Series, Инструкция по эксплуатации

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13
ModBus and BACnet Instructions
6
Wiring Requirements
RS-485 Communication Bus
• Maximum Length = 4000 feet
• Cable Specifi cation = 24 AWG / A,B (twisted pair)
and GND Shielded, with characteristic Impedance
=
120
ohm
• Maximum Load = 32 units (32 nodes)
NOTE: Cable must be terminated with 120 ohm impedance
matching resistor on each end.
Note that when the Tank Temperature is provided by the BAS,
it needs to be refreshed every few seconds. Th
is is required
in order to prevent unwanted fl uctuations in temperature. If
these values are not provided every few seconds (timeout is
programmable), the appliance will revert to its own internal
control. If this temperature is provided by the BAS, but any
of the other control signals are being provided, the BAS will
still need to refresh this input at least every 4 minutes.
Physical Wiring
Figure 7-1 _Terminal Strip Connections
TANK SENSOR
DIR #2000549759 00