Tempco TEC-2500, Instruction Manual, Page: 71 / 108

67
4–9 Analog Retransmission
Analog retransmission is available for model number TEC-2500-XXXXXNX where
N=3, 4 or 5. See ordering code in section 1-2.
Setup
Select FULL for FUNC in the setup menu.
Select a correct output signal for COMM which should be accordant with the
retransmission option used. Five types of retransmission output are available. These
are: 4–20mA, 0–20mA, 0–5V, 1–5V and 0–10V. There are eight types of parameters
that can be retransmitted according to the analog function (AOFN) selected. These
are: PV1, PV2, PV1–PV2, PV2–PV1, SV, MV1, MV2 and PV–SV. Refer to table 1.4
for a complete description. Select a value for AOLO corresponding to output zero and
select a value for AOHI corresponding to output SPAN.
How to determine output signal:
AOLO and AOHI are set to scale output signal low SL (e.g., 4mA) and output signal
high SH (e.g., 20mA) respectively. The analog output signal AOS, corresponding to
an arbitrary value of parameter AOV, is determined by the following curve.
Notes:
The setup values used for AOHI and AOLO must not be equal, otherwise, incorrect
values will occur. However, AOHI can be set either higher or lower than AOLO. If
AOHI is set higher than AOLO it could result in a direct conversion. If AOHI is set
lower than AOLO it could result in a reverse conversion.
Example
A control uses a 4–20mA analog output to retransmit the difference value between
input 1 and input 2 (PV1–PV2). It is required that if the difference value is -100, 4mA
will be transmitted, and if the difference value is 100, 20mA will be transmitted. Make
the following setup for TEC-2500:
IN1U=PU, DP1=NODP, IN2U=PU, DP2=NODP, FUNC=FULL, COMM=4-20,
AOFN=P1-2, AOLO=-100, AOHI=100
NOTES
AOHI
≠
AOLO
AOHI>AOLO:
Direct conversion
AOHI<AOLO:
Reverse conversion
Setup Menu
FUNC
COMM
AOFN
AOLO
AOHI
Terminals
12
13 AO+
AO
Parameter Value
Output
Signal
SH
AOS
SL
AOLO AOV AOHI
Formula:
AOS = SL + (AOV – AOLO)
SH – SL
AOHI – AOLO
AOV = AOLO + (AOS – SL)
SH – SL
AOHI – AOLO
Figure 4.6
Conversion Curve
for Retransmission