Honeywell IAQPoint2 Technical Manual page 55

Affected
Version
Models
• •
•
•
• • • •
• • •
• • •
IAQPoint2 Troubleshooting Guide
Diagnostic
Symptom
Look for 'N' at top of
main display. Check
configuration via
Review\User Config
lines 1 and 2.
The monitor does
not communicate.
Examine termination
resistor switches as
•
described in Figure
17 (wall-mount) and
Figure 20 (duct-
mount)
Examine the analog
slide switches as
shown in Figure 20.
Read Modbus hold-
Unexpected data
ing registers with
values read on
a PC tool such as
Modbus.
ModbusPoll.
Read BACnet objects
Unexpected data
with a PC tool such
values read on
as CAS BACnet
BACnet.
Explorer.
Cause
Tests
Network polarity
is incorrect.
Protocol is wrong.
Baud rate is
wrong.
Address is wrong.
Parity is wrong
Unsupported
command (e.g.
Modbus Write
Multiple Regis-
ters)
Termination is
wrong.
The analog ter-
mination resistors
are across the
digital network.
Incorrect interpre-
tation.
Incorrect interpre-
tation.
IAQPoint2™
Solution
Review wiring and
installation instruc-
tions..
Configure for Mod-
bus or BACnet.
Configure for same
speed as other
devices on the
network.
Configure for a
unique address.
Configure to same
value as Modbus
master.
Use a supported
command.
Each network
segment should
have exactly two
120 Ω termination
resistors.
Slide the switches
to the left.
See Modbus
register table on
page 58.
See BACnet proper-
ties table on page
64..
53