Trane Tracer TD7 User Guide

RLC-
S
VU006A-E
4
7
Interconnecting Wirin
g
C
hilled Water Pump
C
ontrol
NOTICE:
E
quipment Dama
g
e
!
If the microprocessor calls for a pump to start and
water does not fl ow, the evaporator may be damaged
catastrophically. It is the responsibility of the installin
g
contractor and/or the customer to ensure that a pump
will always be running when called upon by the chiller
c
o
ntr
o
ls.
An evaporator water pump output relay closes when
the chiller is given a signal to go into the
A
uto mode
o
f
operation
f
rom any source. The contact is opened to
turn off the pump in the event of most machine level
dia
g
nostics to prevent the build up of pump heat.
The relay output is required to operate the Evaporator
Water Pum
p
(EWP) contactor. Contacts should be
compatible with 115/240 VAC control circuit. Normally,
the EWP rela
y
follows the AUTO mode of the chiller.
W
henever the chiller has no diagnostics and is in the
AUTO mode, re
g
ardless of where the auto command
is coming
f
rom, the normally open relay is energized.
When the chiller exits the AUT
O
mode, the rela
y
is timed
to open in an adjustable (usin
g
TU) 0 to 30 minutes.
The non-AUT
O
modes in which the pump is stopped,
include Reset,
S
to
p
, External
S
to
p
, Remote Dis
p
lay
S
to
p
,
S
topped by Tracer,
S
tart Inhibited by Low Ambient Temp,
and Ice Buildin
g
complete.
Table 5. Pump Relay Operation
Chiller Mod
e
R
ela
y
O
p
eratio
n
Au
t
o
I
nst
a
nt cl
o
se
I
ce Buildin
g
I
nst
a
nt cl
o
se
Tr
a
cer
O
verri
d
e Cl
o
se
S
to
p
Timed O
p
en
I
ce Com
p
lete
I
nstant
Op
en
D
ia
g
nostics
I
nstant
Op
en
When going from Stop to Auto, the EWP relay is
energized immediately. If evaporator water fl ow is not
established in 20 minutes
(
for normal transition
)
or 4
minutes, 15 seconds (for
p
um
p
commanded ON due to
an override safety), the UC800 de-ener
g
izes the EWP
relay and generates a non-latching diagnostic. I
f
fl
ow
returns (e.g. someone else is controlling the pump),
the diagnostic is cleared, the EWP is re-energized, and
norma
l
contro
l
resume
d
.
I
f evaporator water fl ow is lost once it had been
established, the EWP relay remains energized and a
non-latching diagnostic is generated. If fl ow returns, the
d
iagnostic is cleared and the chiller returns to normal
o
p
eration.
I
n
g
eneral, when there is either a non-latchin
g
or latchin
g
d
ia
g
nostic, the EWP relay is turned o
ff
as thou
g
h there
w
as a zero time delay. Exce
p
tions whereby the relay
continues to
b
e ener
g
ized occur with:
•
L
ow
C
hilled Water Temp. diagnosti
c
(non-latching)
(
unless also accompanied by an Evap Leaving Water
Temperature Sensor Diagnostic
)
o
r
•
L
oss o
f
Evaporator Water Flow diagnosti
c
(
non-
latching) and the unit is in the AUTO mode, after
i
nitially havin
g
proven evaporator water
fl
ow.
P
ro
g
rammable
R
elay
s
A
pro
g
rammable relay concept provides for enunciation
o
f
certain events or states o
f
the chiller
,
selected
f
rom a
list of likely needs, while only using four physical output
r
elays, as shown in the fi eld wirin
g
dia
g
ram. The four
r
elays are provided (
g
enerally with a Quad Relay Output
L
LID) as part of the Pro
g
rammable Relay Option. The
r
elay’s contacts are isolated Form C
(
SPDT
)
, suitable
for use with 120 VAC circuits drawing up to 2.8 amps
i
nductive, 7.2 amps resistive, or 1/3 HP and for 240 VAC
circuits
d
rawin
g
up to 0.5 amp resistive.
The list of events/states that can be assi
g
ned to the
p
rogrammable relays can be
f
ound in Table 6. The relay
w
ill be ener
g
ized when the event/state occurs.
I
nstallation El
e
ctrical

Trane Tracer TD7 Specifications

General

Brand	Trane
Model	Tracer TD7
Category	Controller
Language	English