Cashco 764T Temperature Controller - Manual (Page 2)

IOM- 764T 2
The name plate of a 764T only indicates the
rotation to change temperature setpoint. It is rec-
om mend ed that a thermometer be in stalled very
near the location of the 764T. If the 764T utilizes
a thermal well, then the ther mom e ter should also
use a thermal well. If the 764T does not use a
thermal well, then the ther mom e ter should not
use a thermal well.
Recommended pipe tap size is 1/2" NPT for a
thermal bulb without a thermal well.
Recommended pipe tap size is 3/4" NPT for a
thermal bulb with a thermal well.
If the pipe tap size is greater than the size required
by either the thermal bulb or thermal well, a pipe
bushing fi tting is recommended rather than bell
reducers to bring the tap size to that required.
Indoors, controllers without a thermal well
may be oriented in any position.
Outdoors, controllers without a thermal well
should be mounted with the main longitudinal
axis horizontal or be low. Make sure that the
vent port (either A or B) will not take in rain-
wa ter; use an angle fi tting, if necessary.
Indoors, controllers with a thermal well should
be mounted as recommended in Article 1.e.
Outdoors, controllers with a thermal well
should be mount ed at a 45° angle to main
pipe or duct axis, when possible. Make sure
that the vent port (either A or B) will not take
in rainwater; use an angle fi tting if necessary.
The con trol ler can be installed at any angle
below 45° at reduced ther mal sensitivity.
2.
3.
4.
5.
g.
h.
i
j.
6.
7.
8.
9.
10.
Use suitable pipe thread sealant when in stall ing a
ther mal well or a 764T thermal bulb.
CAUTION: When engaging the threaded bulb con-
nec tion into its coupling or thermal well, DO NO
GRASP THE PNEUMATIC HOUSING OR KNURLED
LOCK NUT AND MANUALLY RO TATE THE CON-
TROL LER; ONLY USE A WRENCH (1-3/8") AND
TIGHT EN AT THE HEX SUR FACE PRO VID ED!
! Failure to comply may cause the factory-set cali-
bration to be al tered, re quir ing shop re-calibration.
Ro tate the unit CW (viewed from housing end) to
engage threads.
Clean the pip ing and tub ing of all for eign ma te ri als
in clud ing chips, burrs, dirt, etc. prior to use. Use care
in ap ply ing thread seal ant or TFE tape to pre vent
ex cess ma te ri al from en ter ing the fl ow path.
Figure 3: Alternating Heating?Cooling System with
Split-Range Pneumatic (P/P) Positioners -
"Fail" to Cooling Mode on Loss of Air Supply
KEEP CANTILEVERED PIPE, AIRSET, OR OTH ER
AP PUR TE NANC ES TO A MIN I MUM. It is recom-
mended that the airset supplying in stru ment air be
independently mount ed elsewhere and tubed to the
con trol ler. Failure to comply with this rec om men da tion
may result in the even tu al loosening of the housing
from the thermal bulb, causing the unit to go out of
calibration.
Connect piping/tubing per Tables 1 and 2. Do not
plug or restrict the open (unused) port (A or B) vent
connection. Port "A", Port "B" and "OUT PUT" are
identifi ed on the housing cast ing.
764T's can operate with a lubricated, non-dried air
supply; however, good practice and other system
components (airsets, po si tion ers, relays, etc.) re quire
the use of the highest quality air supply available; i.e.
non-lu bri cat ed compressed air source and desiccant
dried air.
Figure 2: Typical Indirect Heating Application