Honeywell STT700 STT700, Руководство пользователя

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Revision 1 STT700 Temperature Transmitter
User’s Manual
Page 17
Loop wiring is connected to the transmitter by simply attaching the positive (+) and negative (–) loop
wires to the positive (+) and negative (–) terminals on the transmitter module terminal block. Route
the wires through the pre-moded channels on top of the terminal module. Connect the loop power
wiring shield to Earth Ground only at the power supply end.
Note that the STT700 transmitter features SmartLine’s Universal terminal wiring capability and thus
is not polarity-sensitive.
With the single input HART transmitter, four (4) terminal screws will be available on the top of the
module. When either the dual-input HART or the single input DE is supplied, five (5) termination
screws will be included.
Figure 11
–STT700 module terminal connections
This transmitter uses the two mounting screws to connect it to Earth Ground. Grounding the
transmitter for proper operation is required, as doing so tends to minimize the possible effects of noise
on the output signal and affords protection against lightning and static discharge. An optional
lightning protection module is available for use in areas that are highly susceptible to lightning
strikes. As noted above, the loop power wiring shield should only be connected to Earth Ground at
the power supply end.
Wiring must comply with local codes, regulations and ordinances.
The current output signal will operate a floating or ground system.
If the signal appears noisy or erratic, it is recommended to ground the loop at the
negative terminal of the power supply.
Shielding should only be connected to ground at one point to avoid ground loops.