Tempco PCM10001, Инструкция по эксплуатации

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PV Shift
In certain applications it is desirable to shift the con-
troller display value (PV) from its actual value. This
can easily be accomplished by using the PV shift
function.
The SHIF function will alter PV only.
Example: A process is equipped with a heater, a sen-
sor, and a subject to be warmed up. Due to the design
and position of the components in the system, the sen-
sor could not be placed any closer to the part. Thermal
gradient (differing temperatures) is common and nec-
essary to an extent in any thermal system for heat to
be transferred from one point to another. If the differ-
ence between the sensor and the subject is 35°C, and
the desired temperature at the subject to be heated is
200°C, the temperature at the sensor should be 235°C.
You should enter -35°C to subtract 35°C from the ac-
tual process display. This in turn will cause the con-
troller to energize the load and bring the process
display up to the set point value.
The controller will enter failure mode if one
of the following conditions occurs:
1. SBER occurs due to input sensor break
or input current below 1mA if 4–20 mA
is selected or input voltage below 0.25V
if 1–5V is selected.
2. ADER occurs due to the A-D converter
of the controller failing.
Output 1 and output 2 will perform the fail-
ure transfer function as the controller enters
failure mode.
Output 1 failure transfer , if activated, will
perform:
1. If output 1 is configured as proportional
control (PB≠ 0), and BPLS is selected
for O1FT, then output 1 will perform
bumpless transfer. Thereafter, the previ-
ous averaging value of MV1 will be
used for controlling output 1.
2. If output 1 is configured as proportional
control (PB≠ 0), and a value of 0 to
100.0% is set for O1FT, then output 1
will perform failure transfer. Thereafter,
the value of O1FT will be used for con-
trolling output 1.
3. If output 1 is configured as ON-OFF
control (PB=0), then output 1 will be
driven OFF if OFF is set for O1FT and
will be driven ON if ON is set for O1FT.
Failure Transfer
Figure 3.7 PV Shift Application
Manual Control
Operation
To enable manual control, the LOCK parameter should be set
to NONE, then press for 6.2 seconds;
(hand control) will appear on the display. Press for 5 sec-
onds, then the MAN indicator will begin to flash and the lower
display will show . The controller is now in manual
control mode. indicates output control variable for out-
put 1, and indicates control variable for output 2. Now
you can use the up and down keys to adjust the percentage
values for the heating or cooling output.
The controller performs open loop control as long as it stays
in manual control mode.
Exit Manual Control
Pressing the key will cause the controller to revert to its
normal display mode.
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