15
KWE P
/N 3940
46 Ve
rsatronik
502 a
nd 502D
MODBUS G
atewa
y V1
.0 F
eb
2
014 Te
chni
ca
l i
nformation subj
ec
t to
ch
ange
w
ithout noti
ce
Connection Overview—24VAC
Communication connections—Vitodens 200, WB2B, HO1
Modbus
Modbus
Connection
!
"
!
#
"
!
24VAC
4
Refer to manual specific to
boiler control. Ensure necessary
LON communication card
installed.
1 A 3’/91cm CAT-5 cable is
supplied with the gateway.
The RJ45 is plugged into the
control and terminates into
the RJ45 socket inside of the
Versatronik 502 gateway.
2 Versatronik 502 gateway.
3 Field wiring for Modbus
connection to terminals A
and B.
4 Field supplied 24VAC power
supply for Versatronik
gateway.
5 Refer to boiler manual with
respect to installing LON
communications card inside
of boiler control.
Connection Overview
5
1
2
3
Modbus Wiring Connections
(RS-485 Network)
COM 1 terminals A and B are used. It is
to be noted that the A/B naming con-
vention may differ across manufactur-
ers.
A=(+) non-inverting
B=(—) inverting
Termination and Bias:
This device does not have a termina-
tion resistor installed. There are two
weak (4.7Kohm) pull up/down resistors
located on the lines to maintain a bias.
Modbus Wiring Connections