This diagram reflects the UZC4
Fire Alarm Output terminals
wired to a FIRE ALARM
System with a Fail Safe, Normally Open Dry Contact. The circuit is normally closed and
must OPEN to activate the UZC4 FIRE MODE. Be sure to cut the Jumper 1 resistor when
you interlock the UZC4 to the Fire Alarm System. When the UZC4 activates Fire Mode,
the HVAC System will shutdown and all connected dampers will close to Isolate &
Compartmentalize the HVAC Duct System. The Fire Alarm System must reset to NORMAL
before the UZC4 will allow HVAC Operations to resume.
SYSTEM WIRING CONTINUED - Specialty Applications
Using the UZC4’s “FIRE Interlock” Feature to satisfy Building Fire Codes
EWC Controls Inc. 385 Highway 33 Englishtown, NJ 07726 800-446-3110 FAX 732-446-5362 E-Mail- [email protected]
18
NC
NO
C
A
U
X
R
L
Y
E
B
D
O
A
D
M
P
R
M1
M2
M4
M6
M6
M4
M2
M1
M6
M4
M2
M1
RESET
CB1
R
C
24V
24V
FA
FA
MXC
MXR
UZC4
FIRE ALARM
SYSTEM
NC C NO
CUT
Separate 24vac
Transformer
To Line Voltage
Provide over current
protection
The UZC4 has a “FIRE”
interlock feature that allows
the UZC4 to satisfy HVAC Fire
C o d e i n R e s i d e n t i a l &
C o m m e r c i a l b u i l d i n g s .
Coordinate with the Fire
S y s t e m s C o n t r a c t o r t o
interlock the UZC4 into the
building Fire Alarm system as
shown and cut the Jumper 1.
When properly interlocked to
the buildings Fire Alarm
system, the UZC4 becomes
an integral part of the Fire
Safety System. If the Fire
Alarm system activates, the
UZC4 will shutdown the
controlled HVAC system and
force all connected dampers to
t h e c l o s e d p o s i t i o n s ,
effectively isolating the duct
work and the Fan system.
This action will reduce the
spread of smoke advancing
through the building assisted
by Fan and Duct systems that
are not interlocked with a Fire
Alarm system, or equipped
with the capability to do so.
The UZC4 has a set of
dedicated terminals to power
up and control an (EBD)
Electronic Bypass Damper.
The UZC4 will assume control
of the EBD and force it to the
OPEN position during the Idle
periods, Short cycle delays or
Changeover delays. It will also
maintain that open position for
45 seconds at the start of any
t h e r m o s t a t d e m a n d f o r
Heating, Cooling, or Fan only
operation. After 45 seconds
the UZC4 will release control
of the EBD, resulting in a
smooth gradual increase in
static pressure. The 45 second
s t a r t u p d e l a y a l l o w s a
Constant speed fan to start in a
“Quiet Mode” eliminating air
noise upon system startup. It
also eliminates hunting on
variable speed systems and it
enhances the latent cooling
capacity of any HVAC system.
Field Wiring =
Factory Wiring =
4
6
1
WHITE “COMMON” WIRE
NC
NO
C
Pressure Control
Wiring Compartment
“EBD” Motor
WIRE
NUT
GREEN
RED
Using the UZC4’s “ON BOARD BYPASS DAMPER SUPPORT”
Wire up the “EBD” straight to the UZC4 to obtain integrated Bypass Damper operational
support via the UZC4’s bypass firmware. The UZC4 defaults the bypass damper open
during idle periods and releases control to the EBD 45 seconds after the Fan starts. This
action results in a smooth, quiet startup and gradual increase in static pressure.
UZC4
JMP1
Figure 29.
Figure 30.
