Tempco TEC-9300, Инструкция по эксплуатации

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51
5–7 Remote Set
Point
An on-line multiple zone
oven is used to dry paint.
Since heat demand varies at
different positions in the pro-
duction line, multiple zones
with individual controls
should be used to ensure a
consistent temperature pro-
file. If you order a TEC-9300
with a retransmission unit for
the master controller, and
retransmit its set point to
input 2 on the rest of the
slave controllers, each zone
will be synchronized with the
same temperature. Here is an
example at right:
Set the following parameters in the setup menu:
For the master unit For the slave units
FUNC = FULL FUNC = FULL
COMM = 1–5V IN2 = 1–5V
AOLO = 0°C IN2L = 0°C
AOHI = 300°C IN2H = 300°C
PVMD = PV1 PVMD = PV1
SPMD = SP1.2 SPMD = PV2
If a voltage signal (such as in the above example) is sent to slave
units, the slave inputs should be connected in parallel. If a current sig-
nal (e.g., 4–20mA) is sent to slave units, the slave inputs should be
connected in series. Current retransmission is widely used because it
can transmit over a longer distance without voltage drop.
Note: AOHI and IN2H should be set with values higher than the set
point range used.
5–8 Differential Control
In certain applications it is desirable to control a second
process so that its process value always deviates from the
first process value by a constant amount. Water tank 1 is
5.12 meters in height, and the level in water tank 2 needs
to be maintained at 1 meter lower than the tank 1 level.
Set the following parameters in the setup menu:
FUNC = FULL
IN1, IN1L, IN1H: According to sensor 1 signal
IN1U = PU
DP1 = 2-DP
IN2, IN2L, IN2H: According to sensor 2 signal
IN2U = PU
DP2 = 2-DP
OUT1 = REVR
O1TY = 4–20
PVMD = P1-2
SPMD = SP1.2
Adjust SP (here it is 1.00) to control the difference
between PV1 and PV2. Choose P1-2 for PVMD; the PV
display will show the difference value (PV1-PV2)
between PV1 and PV2, and this value will be stabilized to
the set point (here it is 1.00). If you need PV1 or PV2
instead of PV, you can use the display mode to select PV1
or PV2 for display. See section 3-23. The diagram at right
indicates PV2 instead of PV.