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AM25T Solid-State Thermocouple Multiplexer
7
7.2 Data Logger to AM25T Wiring
When powering the AM25T from the same battery as the data logger, connect
the data logger to the AM25T as shown in TABLE
. Two CABLE4CBL-L
cables typically carry control, power, and measurement signals between the
AM25T and the data logger.
Do not reverse the polarity of the +12 volt and ground
wires. Damage to the multiplexer, sensors, and data
logger will occur.
A separate battery can be used to power the AM25T. A separate battery might
be used when the AM25T is installed some distance from the data logger.
Ground must be connected between the data logger and the AM25T (FIGURE
FIGURE 7-1. External Battery Connections
When cables in excess of 152 m (500 feet) are used to connect the data logger
to the AM25T, it may be necessary to compensate for the drop in PRT
excitation voltage.
All AM25T inputs are spark gap protected. To ensure that
the spark gaps fire, the large ground wire between the
AM25T and the data logger must not be greater than 152 m
(500 ft). In applications where lightning protection is not
required, limit the data cable length between the AM25T and
the data logger to 305 m (1000 ft).
WARNING
CAUTION