Cashco 764T Temperature Controller - Manual (Page 9)

IOM-764T 9
Insert housing (1) threaded end into thermal
bulb (12), rotating the num ber of rev o lu tions
recorded in Step 2, this sub-section.
Rotate knurled locknut (16) the same num ber
of rev o lu tions recorded in Step 2, this sub-
section. NOTE: Lock nut (16) should be
nearly/already tight; if lock nut (16) is not tight,
fully tighten. If more/less than 1/2 revolution
of the number recorded in Step 2 is required
to tighten lock nut (16), it is recommended
that the housing (1) be removed from the bulb
(12) and that Steps 23 and 24 be repeated.
Insert PB needle valve (3) into housing (1) and
rotate CW until seated. Back out the needle
valve (3) the number of revolutions recorded
in table of Step 13, this sub-section.
Following the above procedure should bring
the re-as sem bled unit "close" to the dis as-
sem bled setpoint. Re gard less, shop cal i bra-
tion is recommended.
Reinstall output pressure gage (1) using
suit able pipe thread compound or tefl on
tape. DO NOT APPLY EX CESS THREAD
SEAL ANT!
SECTION VI
VI. SHOP CALIBRATION
The Model 764T is a "blind con trol ler"; i.e. non-
in di cat ing. When installed in the pro cess each
ad just ment of the PB needle valve (3) and/or the
adusting screw (2.3) will affect the setpoint; i.e.
the adjustments are inter-acting.
Install a 1/4" pipe plug in the "OUT PUT" port of
the unit.
Provide an 18 psig (1.2 Barg) IAS to the proper
port as determined by Table 1, Sec tion II.
Leave PB as set in Section V.B.26.
Provide a known temperature bath that is equal to
the desired setpoint temperature. The bath must
be steady in its temperature.
Loosen knurled lock nut (16) 1-2 rev o lu tions.
1.
2.
3.
4.
5.
Insert the thermal bulb (12) such that it is im mersed
to the underneath side of the hex surface of the
bulb (12). Place locking pliers on the hex surface
of bulb (12) to hold fi rmly.
Rotate adjusting screw (2.3) CW or CCW to
achieve desired set point. If set point cannot
be achieved, go to step b or c.
If the output pressure gage (11) is at 15 psig
(1.03 Barg) or more, decrease the setpoint
tem per a ture by holding the thermal bulb (12)
with locking pliers, and ro tat ing housing (1)
CW (viewed from front face) until the output
pres sure de creas es to 9 psig (0.62 Barg).
If the output pressure gage (11) is at 0 psig
(0.0 Barg), increase the setpoint temperature
by hold ing the thermal bulb (12) with locking
pli ers, and ro tat ing housing (1) CCW (viewed
from front face) until the output pressure in-
creas es to 9 psig (0.62 Barg).
FOR DIRECT ACTION:
6.
7.
a.
b.
c.
8.1.
Pick up housing (1) and insert sensor plate
subassembly (15) back into the housing (1).
Insert new sensor plate O-ring (6) up against
the sensor plate (15.1).
Holding the housing (1) with the cavity up-
wards, re-insert sensor subassembly (2)
into the housing (1) cavity. Push fi rmly until
the sensor subassembly (2) end plate (2.2)
reach es the mating face of the housing (1). DO
NOT FORCE INSERTION OF THE SENSOR
SUBASSEMBLY (2). IF NOT CEN TERED
IN HOUSING (1) CAVITY, DAM AGE MAY
OC CUR TO SENSOR O-RINGS (5)!
Rotate sensor end plate (2.2) until the thread ed
hole for screw (9) is directly above the propor-
tional band needle valve (3) opening. Holes
should align for the four end plate screws (8);
rotate as required. Insert screws (8) and fully
tighten in a cross pattern.
(Remove temporary tape of Step 18 pre vi ous
this sub-section.) Re-position name plate (10)
onto sensor end plate (2.2) and align screw
(9) hole; insert and tighten screw (9).
19.
20.
21.
22.
23.
24.
25.
26.
27.