WIRING AND ADJUSTMENT INFORMATION
CAUTION: The use of non thermocouple wire will cause inaccurate temperature sensing and erratic operation.
3.When connecting the thermocouple extension wire to your thermo- couple leads, twist the wire connections, then install wire nuts, such as ceramic type, which have no metal insert.
DO NOT SOLDER.
To prevent problems of interference from electrical noise, DO NOT route thermocouple wires in the same conduit or within 12 inches (304 mm) of ignition wires or alternating current conductors.
B.Connecting Thermocouple Wires (ungrounded thermocouple)
1.Remove factory installed jumpers or shunts from TC1 and TC2 terminals before connecting thermocouple(s).
2.Connect the thermocouple leads to the thermocouples. Observe lead polarity. See Table 1 for thermocouple extension lead color code and thermocouple polarity.
NOTE: Before continuing to the next step, decide which thermocouple is to be identified as TC1 and which is to be identified as TC2. A wire marker should be installed on each end of the thermocou- ple lead to identify TC1 and TC2.
3.Connect the positive lead of thermocouple TC1 to the positive (+) terminal of terminal strip TC1.
4.Connect the negative lead of thermocouple TC1 to the negative
5.Connect the positive lead of thermocouple TC2 to the positive (+) terminal of terminal strip TC2.
6.Connect the negative lead of thermocouple TC2 to the negative
C.Connecting Output Wires
Wire the SWICHGAGE® trip point outputs as shown in the typical wiring diagrams on the back of this page.
D. Connecting Power Wires
1.Determine the voltage and the polarity of the input power before attempting to connect the power leads to the MDTM89.
2.On CD ignitions, connect the shutdown lead to the MDTM89 ignition input as shown in the diagrams below.
Operation Test
NOTE: Perform the Operation Test after the MDTM89 is installed and wired appropriately.
1.a. Rotate the trip point potentiometers TC1 and TC2 clockwise until an audible click is heard or detente is felt. These are
b.Start the engine or power up the monitor.
2.a. Set the display selector switch to the TC1 position to display the TC1 temperature.
b.Next depress and hold the “Push to Read” trip point push button to display the TP1 setting.
c.Rotate the TC1 trip point potentiometer counterclockwise until the display reading is equal to the temperature reading observed in step 2. a.
d.Trip point TP1 will turn on and trip the shutdown device or alarm; verify by observation.
e.Rotate the trip point potentiometer TC1 clockwise several turns to turn off TP1.
f.Reset alarm or shutdown device.
3.a. Set the display selector switch to the TC2 position to display the TC2 temperature.
b.Next, depress and hold the “Push to Read” trip point push button to display the TP2 setting.
c.Rotate the TC2 trip point potentiometer counterclockwise until the display reading is equal to the temperature reading observed in step
d.Trip point TP2 will turn on and trip the shutdown device or alarm; verify by observation.
e.Rotate trip point potentiometer TC2 clockwise several turns to turn off TP2.
f.Reset alarm or shutdown device.
TRIP POINT ADJUSTMENT INFORMATION
Trip Point Adjustments
1.Power up the temperature monitor by turning on power or by starting engine.
2.Set the display selector switch to the TC1 position.
3.Depress the “Push to Read” trip point push button to read trip point.
4.Rotate the trip point potentiometer TC1 until the display indicates the desired trip point temperature for TC1.
5.Set the display selector switch to TC2 position.
6.Depress the “Push to Read” trip point push button to read the trip point.
7.Rotate the trip point potentiometer TC2 until the display indicates the desired trip point temperature for TC2.
Face Plate Diagram
A. Trip point/display toggle switch.
B. Readout digital display.
C. Trip point potentiometers.
D. Push to read trip point button.
B
A
DETAIL
12turn
potentiometers
C
D