In Case of Difficulty
Check that the COM port you are using matches the COM
port selected in the SETUP screen.
A null modem adapter (not supplied) may be required to
match the outputs of your computer's serial port to the
To determine if this is necessary, proceed as
Connect the 4100SM to the control panel and to your
PC as described previously in this document. Do not
attach a null modem adapter.
Connect a DC voltmeter, set to a 15-volt (or higher)
range, across the black wire on 4100SM terminal 7(–),
and the wire on terminal 3(+). No voltage should be
seen at this time. If a voltage is found, check the
connections between the control and the 4100SM.
Go to the COMM screen after selecting DIRECT WIRE
and hit the [ENTER] key two times until the
REQUESTING SESSION message appears. At this
time, the meter reading should jump to approximately
12 volts for few seconds and then return to zero. If this
does not occur, there is a possibility that the transmit
and receive pins on the computer are reversed. Insert a
Null Modem adapter (not supplied) and try again.
N5391V4 5/15 Rev A
For the latest warranty information, please go to:
2 Corporate Center Drive, Suite 100
P.O. Box 9040, Melville, NY 11747
Copyright © 2015 Honeywell International Inc.
4" W x 2-3/4" H x 3/4" D (102mm x 70mm x 19mm)
Input Power: 12VDC, 25mA from control's keypad
power (red wire) connection
DB25 female with DCE output