Advanced Power technologies TTC-1000, Instruction & Operation Manual, Page: 110 / 262

V6.230 20131017
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7 TELEMETRY OPTIONS
This section will discuss the various telemetry options available, their use and
any relevant settings. The TTC-1000 can be optionally equipped with current
loop outputs and a RS-485 DNP3.0 or MODBUS communications interface. All
TTC-1000’s come equipped with a 9 pin DB-9 connector for RS-232 ASCII
communications. Temperature information can be retrieved through the RS-232
interface.
7.1 Analog Outputs
The TTC-1000 is available with up to three analog outputs configured as current
loops. The source for each analog output can be selected from probe 1 (P1),
probe 2 (P2), probe 3 (P3), or calculated winding temperature. The analog output
is designed to operate with a series resistance of 10,000 Ohms when set to 0 to
1 mA or 510 Ohms when set to 4 to 20 mA. The third analog output is configured
to supply 0 to 1 mA and cannot be switched to operate in the range of 4-20 mA.
NEMA units with serial letter suffix ‘B’ contain TB4 for connections to the analog
outputs. All other NEMA units utilize TB2. The terminal is the current
source output. The connection marked – is the current transmitter’s return. These
outputs are fully isolated, but the return may be connected to chassis ground at
the RTU. Grounding the return inside the TTC-1000 is not recommended.
NOTE: Connect to the analog outputs through shielded cable. Connect the
drain wire of the shield to the ground stud inside the NEMA 4 enclosure or
to one of the studs on the rear of the panel mount version. Twisted pair
cable is recommended. See section 3.10 for proper shield grounding.
All analog outputs can be programmed for 0 to 1 mA or 4 to 20 mA. The outputs
are set as a group such that all are 0-1 or all are 4-20.
The scaling of the analog output varies depending on what is being measured.
The following table illustrates the scaling dependent on range and the quantity
measured and whether negative temperature scaling is enabled