Mode; Offset; Reference-Junction Temperature; Material - Ectron 1140A Instruction Manual

Thermocouple simulator-calibrator

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Operation

°C or °F as described above) must be pressed to change the reading. To abort any entry, press

ESC at which time the Model 1140A will revert to the last saved entry.

Mode

The Model 1140A operates in two modes: source and measure. In the source mode, the

Model 1140A produces a voltage output; in the measure mode, it accepts a voltage input. The

voltage is either in volts, millivolts, or in temperature (the emf equivalent for the type

thermocouple that is active).

The active mode is displayed in the upper left corner of the main display.

The offset is used to compensate for any inaccuracies attributable to the instrumentation being

used. For example if the thermocouple wire being used has been found to have +0.035°C error,

that offset in the opposite polarity should be entered so that in the source mode, the meter being

calibrated will read correctly, and in the meter mode, the Model 1140A will correctly display the

temperature or voltage of the thermocouple being measured. Each thermocouple type has its own

offset.

The offset is displayed in the lower middle right of the main display.

The reference-junction temperature is the temperature at which the Model 1140A simulates the

copper-to-thermocouple-wire (alloy) connections when using thermocouple wire. The connection

is most often at the Model 1140A binding posts or thermocouple connector. The Model 1140A

constantly measures the actual temperature of the terminals to provide precision compensation.

Unless the user's setup has the copper-to-thermocouple-wire junctions remote to the

Model 1140A, the reference-junction temperature should be set to 0°C. The allowable reference-

junction temperatures is the temperature range for the thermocouple type being used and can be

displayed in °C, °F, °R, K, or system units. The system units are whatever is set in the

INSTRUMENT MODE MENU. Note that the reference-junction temperature is only used when the

output-entry mode and the material differ in nature (temperature and copper connections or

voltage and alloy connections).

The reference-junction temperature is displayed in the lower middle left of the main display.

Either copper wires or alloy (thermocouple) wires can be connected to the Model 1140A. The

user should set the MATERIAL to match the wiring being used.

The material is displayed in the lower right of the main display.

Table

4-1

lists the thermocouple types available in the Model 1140A. The active thermocouple

type is displayed in the lower left corner of the main display.

4-4

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