IM 738-2
55
Electrical Installation:
Field Control Wiring
Field Control Wiring
Roof Pak applied rooftop units are available with several
control arrangements which may require low voltage field
wiring. Detailed descriptions of various field control wiring
options and requirements are included in the “Field Wiring”
section of Bulletin No. IM 696, “MicroTech II Applied
Rooftop Unit Controller.” Refer to the unit wiring diagrams for
additional installation information.
Wiring must comply with applicable codes and ordinances.
The warranty is voided if wiring is not in accordance with
these specifications.
RPS, RDT, and RFS Units
All field control wiring connections are made at the class II
terminal block TB2, which is located in the main control panel.
Field wiring connections to the 115 volt receptacle and lights
are made at terminal block TB7, which is located also in the
main control panel. Refer to Figure 68
.
Two 7/8" knockouts are provided for wire entry.
RFS/RCS Units
The RCS unit receives 115V and 24V control circuit power and
a number of control signals from the RFS unit. Two 7/8"
knockouts are provided in the right side of the RCS control box.
Interconnecting wiring enters the RFSunit through 7/8"
knockouts in the bottom of the main control panel. The
interconnecting wiring is connected to TB4 in the RFSunitand
TB5 in the RCS unit. Refer to Figure 69. A 7/8" knockout is
also available in the end of the unit base as shown in Figure 68.
Note:
If a single conduit containing 24V and 115V wiring is
run above the roofline between the RFS and RCS unit,
install the 24V wiring as an NEC Class I wiring system.
Figure 68. RDT, RFS, RPS field control wiring connections
Figure 69. RFS and RPS interconnecting control wiring
WARNING
Electrical shock hazard. Can cause severe injury or death.
Connect only low voltage NEC Class II circuits to terminal
blocks TB2 and TB5.
Reinstall and secure all protective deadfront panels when the
wiring installation is complete.
M a i n o n t r o l
P a n e l
4 V F i e l d
T e r m i n a l
B l o c k
( T B )
o n t r o l W i r i n g R a c e w a y
o v e r ( R e m o v e f o r a c c e s s
t o h a r n e s s f r o m m a i n c o n t r o l
b o x t o u n i t m o u n t e d
c o n t r o l d e v i c e s )
TB5
24V
115V
PB4/DS4P
Condenser
control
panel
DS2
PB1/DS1
TB4
Main
control
panel
RFS Unit
RCS Unit