Cashco 764T Temperature Controller User Manual
Page 3
IOM-764T
3
Instrument air exposed to outdoor freezing tem-
per a tures must be desiccant dried. Re frig er at ed
drying is not ad e quate.
Instrument air exposed to indoors and/or no-freezing
tem per a tures is recommended to be re frig er ant
dried as a minimum.
If the air supply is at a remote location, and can
not be practically dried and bears oil (i.e. plant air),
co a lesc ing fi lters must be utilized to re move as
much oil and water as possible, as well as par ti cles
over 15 mi crons size.
Figure 4: Recommended Thermal Well (Opt. 64) Installation
TABLE 1
Controller
Model 764T
ISA to
Port
Action
Direct
Reverse
A
Exhaust
Supply
B
Supply
Exhaust
PROCESS
TEMPERATURE
Increase in
temperature
increases output
signal
Increase in
temperature
decreases output
signal
TABLE 2
Controller
"Heating Applications"
IAS to
Port
Actions
Control Valve
Controller
A
ATO-FC
(Reverse)
Reverse
Increase in temperature
decreases output signal.
Valve "fails" to "cooler"
process temperature.
B
ATC-FO
(Direct)
Direct
Increase in temperature
increases output signal.
Valve "fails" to "hotter"
process temperature.
B
"Cooling" Applications
Actions
ATO-FC
(Reverse)
Direct
Decrease in temperature
decreases output signal.
Valve "fails" to "hotter"
process temperature.
A
ATC-FO
(Direct)
Reverse
Decrease in temperature
increases output signal.
Valve "fails" to "cooler"
process temperature.
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