Tek-Trol Tek-LCD 7802A, Instruction Manual, Page: 12 / 43

3 Connections
WARNING
•
Static electricity can damage sensitive components.
•
Observe safe handling precautions for static-sensitive components.
•
Use proper grounding procedures/codes.
•
If the meter is installed in a high voltage environment and a fault or installation error
occurs, high voltage may be present on any lead or terminal.
To access the connectors, remove the enclosure cover and unscrew the two captive screws that fasten
the display module. Disconnect the ribbon cable and remove the display module. Signal connections
are made to a four-terminal connector in the base of the enclosure.
4-20 mA signal input positive terminal connection
SIGNAL - 4-20 mA signal return/negative terminal connection when not using loop
powered backlight.
BAC +9-30 VDC when powering backlight from external supply.
BACKLIGHT -
4-20 mA signal return/negative terminal when using the installed loop powered
backlight or ground/negative when powering backlight from external supply.
NPN open collector output positive.
OUTPUT- NPN open collector output negative.
RESET + Contact closure reset pullup to 3 VDC
RESET- Contact closure reset ground/negative.
Refer to Figure 1 for terminal positions.
WARNING
Observe all safety regulations. Electrical wiring should be performed in accordance with all
agency requirements and applicable national, state, and local codes to prevent damage to the
meter and ensure personnel safety.