Trane Tracer TD7 User Guide

RLC-
S
VU006A-E4
1
0
I
nstallation El
e
ctrical
These customer-supplied contact closures must
be compatible with 24 VDC, 12 mA resistive load.
Silver or gold plated contacts are recommended.
Ice Buildin
g
Optio
n
UC800 provides auxiliary control for a customer
specifi ed/installed correct with contact closure 5K20 for
ice building i
f
so con
fi
gured and enabled. This output
is known as the Ice Building
S
tatus Relay. The normally
open contact will be closed when ice building is in
progress and open when ice
b
uilding has
b
een normally
terminated either through
I
ce
T
ermination setpoint
b
eing
reached or removal of the Ice Buildin
g
command. This
output is
f
or use with the ice storage system equipment
or controls (provided by others) to signal the system
chan
g
es required as the chiller mode chan
g
es
f
rom
“
ice
b
uilding
”
to
“
ice complete
”
.
W
hen contact 5
K
12 is
p
rovided, the chiller will run normally when the contact
i
s open.
U
C
800 will accept either an isolated contact closure
(External Ice Building command) or a Remote
Communicated in
p
ut (Tracer) to initiate and command
the
I
ce
B
uildin
g
mode.
UC800 also provides a “Front Panel Ice Termination
S
etpoint”, settable through Tracer™ TU, and adjustable
from 20 to 31°F
(
-6.7 to -0.5°C
)
in at least 1°F
(
1°C
)
i
ncrements.
Note:
When in the Ice Building mode, and the
:
e
vaporator entering water temperature
d
rop
s
b
elow the ice termination setpoint, the chille
r
t
erminates the
I
ce
B
uildin
g
mode and chan
g
e
s
t
o the Ice Building
C
omplete Mode.
N
O
TICE
:
Equipment Dama
g
e!
Freeze inhibitor must be adequate for the leaving water
temperature. Failure to do so will result in dama
g
e to
system com
p
onents.
T
racer
™
TU
must als
o
b
e used t
o
ena
b
le
o
r disa
b
le
I
ce
Machine Control. This settin
g
does not prevent the Tracer
f
rom commandin
g
Ice Buildin
g
mode.
Upon contact closure, the U
C
800 will initiate an ice
building mode, in which the unit runs
f
ully loaded at all
times. Ice buildin
g
shall be terminated either by openin
g
the contact or
b
ased on the entering evaporator water
temperature. U
C
800 will not permit the ice building
mode to
b
e reentered until the unit has
b
een switched
out of ice building mode (open 5K12 contacts) and
then switched back into ice buildin
g
mode (close 5K12
contacts.)
In ice buildin
g
, all limits (freeze avoidance, evaporator,
condenser, current) will be ignored. All safeties will be
enforced.
If, while in ice building mode, the unit gets down to the
freeze stat setting (water or refrigerant), the unit will
shut down on a manually resettable diagnostic, just as in
normal o
p
eration.
Connect leads from 5K12 to the proper terminals of
1A15. Refer to the fi eld diagrams which are shipped with
t
he unit.
Silver or gold-plated contacts are recommended. These
customer furnished contacts must be com
p
atible with
2
4 VD
C
, 12 mA resistive load.
External Chilled Water
S
etpoint
(
ECWS) Optio
n
The U
C
800 provides inputs that accept either 4-20 mA or
2
-10 VDC signals to set the external chilled water setpoint
(ECWS). This is not a reset function. The in
p
ut defi nes the
setpoint. This input is primarily used with generic BAS
(
building automation systems
)
. The chilled water setpoint
set via the
T
racer
TD
7 or throu
g
h di
g
ital communication
with Tracer
(
Comm4
)
. The arbitration of the various
chilled water set
p
oint sources is described in the fl ow
charts at the end
of
the secti
o
n
.
The chilled water setpoint may be chan
g
ed
f
rom a
r
emote location by sending either a 2-10 VD
C
or 4-20 mA
si
g
nal to the 1A14, terminals 5 and 6 LLID. 2-10 VD
C
and
4
-20 mA each correspond to a 10 to 65°F (-12 to 18°C)
external chilled water set
p
oint.
The following equations apply:
Voltage
S
ignal
As
g
enerated from external source VDC=0.1455*(ECWS) + 0.545
4
As
p
rocessed by UC800 ECWS=6.875*(VDC) - 3.7
5
Current Signal
As
g
enerated from external source mA=0.2909(ECWS) + 1.090
9
As
p
rocessed by UC800 ECWS=3.4375(mA) - 3.75
I
f the ECWS input develops an open or short, the LLID
will report either a very high or very low value bac
k
to
t
he main processor. This will
g
enerate an informational
d
iagnostic and the unit will de
f
ault to using the Front
P
anel
(
TD7
)
Chilled Water Setpoint
.
Tracer TU Service Tool is used to set the input signal type
from the factory default of 2-10 VDC to that of 4-20 mA.
T
racer
TU
is als
o
used t
o
install
o
r rem
o
ve the
E
xternal
Chilled Water Set
p
oint o
p
tion as well as a means to
enable and disable ECW
S
.
External Demand Limit Set
p
oint
(
EDLS
)
O
p
tio
n
Similar to the above, the UC800 also provides for an
optional External Demand Limit Setpoint that will accept
either a 2-10 VDC (default) or a 4-20 mA signal. The
D
emand Limit
S
etting can also be set via the Tracer TD7
or throu
g
h di
g
ital communication with Tracer (Comm4).
The arbitration o
f
the various sources o
f
demand limit is
d
escribed in the fl ow charts at the end of this section. The
External Demand Limit
S
etpoint may be changed from a
r
emote location by hooking up the analog input signal to
t
he 1A14 LLID terminals 2 and 3. Re
f
er to the
f
ollowin
g
para
g
raph on Analo
g
Input Si
g
nal Wirin
g
Details.

Trane Tracer TD7 Specifications

General

Brand	Trane
Model	Tracer TD7
Category	Controller
Language	English