Specifications; Communication Protocol; Led Indicators - Honeywell IAQPoint2 User Manual

Specifications

Communication Protocol

Communication Protocol
The 301ADI communicates with Honeywell 301C controller through
Modbus RTU communication protocols. The controller continuously
"polls" to read devices connected to it. The unit's Modbus address can
be changed through the programming interface (accessible only when
the unit is open).
Communication cables must be grounded using the shield terminal.
Use twisted and shielded (Belden 9841) #24/2 AWG cable to wire the
connection. The network can be up to 2000 feet (600m) per channel.
The length of a T-tap cannot exceed 65 feet (20m), and the maximum of
130 feet (40 m for all T-taps must be respected.

LED Indicators

The 301ADI has three externally visible LED indicators, or lights. Each
LED communicates a specific function, as shown in the table below:
LED
Number/ Indication
Color
LED 1 -
Power
green
LED 2 -
Fault
Amber
LED 3 -- Tx
Amber Modbus
20
Specifications
Description
If the light is on, unit is powered up
and functional.
Indicates a possible fault on one of
the 4-20 mA inputs. Typically when
nominal current is below 3 mA.
Light is on when the 301ADI
responds to a poll on the Modbus
port. (The LED shows not polls but
replies from the unit itself. This is
useful when selecting an address
because it allows troubleshooting
the communication setup.)
301ADI User Manual
Honeywell
Circuit
Board
Position
D2
D3
D4
510846
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