Wiring Guide

© 2009 W 423 - 03/09 8 of 12
Wiring tekmarNet
®
4 (tN4) Between Devices Terminals 58 - 65
Wiring the Control Terminals 50 - 78
The following section explains how to wire individual
devices to the Universal Reset Module 423. For step by
step wiring refer to the terminal number on the right of
the page.
•
• Before wiring ensure all power is turned off and take all
necessary precautions.
•
• Install the supplied wiring compartment barriers by sliding
them into the grooves provided as to isolate the low and
high voltage wiring.
•
• Strip all wiring to a length of 3/8 in. or 10 mm for all
terminals.
•
• Refer to the current and voltage ratings at the back of this
brochure before connecting devices to this control.
Terminals 58 through 65 provide four tN4 connections for
tN4 devices on either the Boiler bus, tN4 bus 1, tN4 bus
2, or tN4 bus 3.
•
• Connect terminals 58 (C) and 59 (tN4) to the correspond-
ing terminals on other tN4 devices on the Boiler Bus.
•
• Polarity is important.
•
• Connect terminals 60 (C) and 61 (tN4) to the correspond-
ing terminals on other tN4 devices on the Bus 1.
•
• Polarity is important.
•
• Connect terminals 62 (C) and 63 (tN4) to the correspond-
ing terminals on other tN4 devices on the Bus 2.
•
• Polarity is important.
•
• Connect terminals 64 (C) and 65 (tN4) to the correspond-
ing terminals on other tN4 devices on the Bus 3.
•
• Polarity is important.
Wiring the Boiler Terminals 50 - 51, 52 - 53
Terminals 50-51 and 52-53 are dry contacts. No power is
available from these switches. When the switch at 50-51 or
52-53 is closed the boiler is to turn on. The boiler gets no
power from these terminals and the boiler must be wired
to power as per the manufacturers’ directions.
These terminals are typically connected to the boiler’s
control circuit (commonly labeled as T-T). Connect these
terminals directly to the boiler T-T connections.
Stage 1/
Boil Enbl
50
51
T-T contacts on boiler
Stage 2/
Setp Enbl
52 53
T-T contacts on boiler
Wiring the Modulating Boiler Output Terminals 54 - 57
•
• The control provides a 0-10 V (dc) modulating output
to two modulating boilers or to a tekmar boiler staging
control that accepts an External Input Signal in place of
an outdoor sensor. (Example: 264, 265 and 268)
•
• Polarity is important.
•
• Connect the + wire from the boiler or staging control
to terminal 54 and the – wire from the boiler or staging
control to terminal 55.
•
• Connect the + wire from the boiler to terminal 56 and
the – wire from the boiler to terminal 57.
Note: Some modulating boilers may also require an on / off
signal in addition to the modulating signal. See terminals
50-51 and 52-53.
+-
Mod1 (dc)
54 55
Modulating Boiler or tekmar Stager
+-
+-
Mod2 (dc)
56 57
+-
Modulating Boiler
typical tN4 connection
on additional control
C2 tN4
Boiler
58 59
C tN4
C tN4
1
60 61
C3 tN4
2
62 63
C4 tN4
3
64 65