Martel Electronics 3001 - Manual (Page 26)

selected. If RTD/O mode is displayed, press the key again to cycle to thermocouple
mode.
c) If output mode is displayed, select input mode by pressing the and
keys.
d) Press the key to select the desired thermocouple type or the millivolt range.
e) Connect the unit under test to the thermocouple terminals of the 3001 using a
standard T/C miniplug as shown in figure 14. One pin is wider than the other; do not
attempt to force the plug in the wrong polarization. The T/C wire used for the
connection must match the thermocouple type selected for proper cold junction
compensation. If the 3001 and the T/C miniplug are at different temperatures, wait at
least 3 minutes for the miniplug and terminals to stabilize to the same temperature.
Figure 14 - Thermocouple Input Connection
f) Press the and keys to toggle the thermocouple display between °F and
°C.
g) Press the and keys to toggle the cold junction compensation between
the internal temperature sensor and an external reference.
h) For best accuracy, it is advisable to zero the T/C millivolt circuit daily, or if the 3001 is
being used outside of the ambient temperature range of 18 to 28 °C. The maximum
offset from unit calibration that can be zeroed out is ±1 mV.
To zero the T/C millivolt circuit:
• Select the thermocouple measure function as described above, and press the
key until the millivolt range is selected.
• Insert the supplied thermocouple shorting jumper into the thermocouple terminals.
• Allow at least 3 minutes for the jumper and terminals to stabilize to the same
temperature.
• Press the and keys to zero the T/C millivolt circuit.
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