Johnson Controls UNT110-1 User Manual

UNT Controller—Unitary (UNT) Controller
31
!
CAUTION: Some local electrical codes and NEC 250 require the
secondary common of stepdown transformers be
connected to earth ground on units which are powered
by greater than 150 VAC. You may have a maximum
of one single earth ground connection, which must be
at the transformer secondary common, whether one or
multiple controllers are powered by the same
transformer.
wi reunt 1
BINARY OUTPUTS
On unit mounted controls, OEMs typically minimize
wiring between digital controls and equipment interface
relays by using one leg of the stepdown transformer
as common.
L1 L2
Unit Mounted Control Enclosure
See the
Application Examples
section for more i nformation.
UNT Controller
Triac Switching
ZBUS
REF
N2 - N2+
COM 24
VAC
COM
24 VAC
LED
Internal Shared Triac Node
COMPRESS
Comp.
Relay
Heat
Relay
Fan
Relay
Jumper allows field selection of the supply leg to
be switched by the triacs. In this example, the
triacs terminal is jumpered to "24 VAC", so the
triacs switch the 24 VAC power (high side) leg.
COMMON
Stepdown
Transformer
FAN
HEAT
24 VAC
See
CAUTION
for
Wiring to Unit
Mounted Controls--
UNT110/111 and
UNT120/121
section.
Internal Wiring Connections
Figure 10: Binary Output Triac Connections on “Quick Connect”
Versions of the UNT110/111 and UNT120/121
Wiring to Unit
Mounted
Controls--
UNT110/111 and
UNT120/121

Johnson Controls UNT110-1 Specifications

General

Brand	Johnson Controls
Model	UNT110-1
Category	Controller
Language	English