CTH3-SERIES INSTALLATION, OPERATION AND SERVICE MANUAL

10.4.9 Potentiometer Control Device

Potentiometer (10K Ohm"Linear Taper") device offers manual control over heater(s) firing rate. This type of potentiometer can be found at Radio Shack® .

Potentiometer dial position directly dictates heater(s) firing rate. Dial positions range between "Min" and "Max". Minimum and maximum heater firing rates (inputs) are marked on the heater's rating plate. ON/ OFF switch or thermostat is used to disable heater operation or reset heater from lockout.

FIGURE 28: Potentiometer Control Wiring Diagram

ON/OFF SWITCH

CENTRAL HEATER CONTROL

or THERMOSTAT

 

 

 

 

 

THERMOSTAT

 

 

 

 

T24

 

 

 

 

 

R

 

 

 

T25

 

 

 

 

 

W

 

 

 

T26

 

 

 

 

T27

ANALOG INPUT + -

 

 

 

 

 

T13

TH

 

 

ERMISTO

 

 

T14

 

 

R

 

POTENTIOMETER

 

GND

 

 

(10K Ohm)

T15

 

 

 

 

SLIDE BAR

 

 

 

 

 

T16

 

 

 

 

 

GND

 

 

 

T17

 

 

 

 

 

HIGH

 

 

 

T18

WIPER

EXT. POT

 

 

T19

 

 

 

GND

 

 

 

T28

 

 

 

 

 

+

 

J10 JUMPER POSITION

 

 

RATE IN -

FIRING

 

T29

SHOWS "CENTRAL"

 

 

DESIGNATION AND

 

 

 

 

"POTENTIOMETER"

 

T30

 

 

CONTROL METHOD.

 

 

+

 

 

 

T31

RATE OUT

A B

 

 

 

IFRING

 

 

 

-

 

 

 

 

 

J10

 

 

MODULATION CONTROL WIRING

 

 

TO SATELLITE HEATERS

 

SATELLITE HEATER CONTROL

*OPTIONAL

 

SWITCH

 

THERMOSTAT

 

T24

 

 

R

T25

 

 

W

T26

 

T27

ANALOG INPUT + -

 

T13

TH

ERMISTO

T14

R

 

GND

T15

 

 

SLIDE BAR

T16

 

 

GND

T17

 

 

HIGH

T18

EXT. POT WIPER

T19

 

GND

T28

 

 

+

T29

FIRING RATE IN

 

 

-

T30

J10 JUMPER POSITION

 

SHOWS "SATELLITE" DESIGNATION.

 

+

T31

A B

 

IFRING ERAT OUT

 

-

 

J10

 

MODULATION CONTROL WIRING

 

TO ADDITIONAL SATELLITE

 

HEATER CONTROL TERMINALS

 

T28 AND T29.

* Separate on/off switch is optional for "satellite" heaters (install at user level).

On/Off switch is used to disable heater operation or reset a heater that is in "lockout" mode. If on/off switch is not desired, leave jumper wire between R and W terminals in place.

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Aiko CTH3-200, CTH3-150, CTH3-80, CTH3-115 service manual Potentiometer Control Device, Potentiometer Control Wiring Diagram