16502 PIREG-C2 Gerätebeschreibung mit EtherNet_IP Bussystem191017 - EN.docx/ Page 58 of 66
Prior to initial operation, the correct temperature coefficient must be set for the heating conductor being
used. Setting too high a temperature coefficient may lead to overheating or melting of the heating conduc-
tor.
In addition, the temperature comparison time, the temperature range, the calibration type and the trans-
former type must be set. If necessary, the variable reference temperature and the 8-point Tc correction
must also be activated. A signal must therefore be applied to the set point input. The setting for the heat-
ing ramp can be made before or after calibration.
5.4. Connecting the PIREG-C2
The resistance temperature controller must be connected according to the connection diagram, depend-
ing on the type of actuator used. It is not necessary to pay attention to the polarity of the current Ir and
voltage Vr measurement cables to the heating conductor, nor to how the sealing transformer is connected
on the primary or secondary side.
When connecting a target value potentiometer, it is vital to pay attention to the correct phase sequence.
In the 0 °C setting, the resistance between terminals 13 and 16 must be 0 Ω.
The measurement cables for voltage measurement Vr must be connected directly to the heating conduc-
tor and have to be twisted. (50 turns/m). The cables from the sealing transformer should be connected
to the heating conductor with cable lugs and not with plug-type connections. Ensure that the conductors
are of adequate cross-section. No additional components, such as fuses, switches or resistance-loaded
ammeters should be integrated in the secondary circuit of the sealing transformer.
5.5. Control inputs
Ensure that there are no high signals applied to the reset and start control inputs before the controller is
started up for the first time. (If the calibration to an altered heating band is not appropriate, it may over-
heat).
5.6. Connecting to the mains voltage
The green Power LED will light following connection to the mains.
If “new calibration” is chosen as calibration mode, the PIREG-C2 will start the calibration procedure im-
mediately after the power has been switched on and it will adjust the controller to the combination of seal-
ing transformer and heating conductor. The blue Calibration LED will light up and the yellow Heat LED will
flash. After successful calibration, the PIREG-C2 will return to the OFF state and be on standby (see Fig.
1).
If "Store calibration" is chosen as calibration mode, the PIREG-C2 will return to the off or error state after
the power is switched on and will wait for the "Calibration start" signal. The alarm and calibration LEDs
may be off, on or flashing. If there are no errors from 1 to 3 (see Error State table 1), then the calibration
can be activated.
5.7. Burning in the heating conductor
With the sealing tool held open, the heating conductor should best be "burned in" in such a way that the
"Start" signal is given and the nominal temperature is slowly increased from zero to the burn-in tempera-
ture. The final burn-in temperature should be at least 50°C above the maximum sealing temperature on
the heating conductor. The heating conductor should be monitored (initial colours, hot spots). Calibration
should be carried out again following burn-in.
The initial slow increase of the target temperature is also recommended if a thermally pretreated heating
conductor is used which does not need to be burnt in. In this way the correct temperature conductance of
the heating conductor can be monitored. Errors arising during calibration and the selection of the temper-
ature coefficient can be checked without the heating conductor can get overheated or burn up ( 6.).
5.8. When the controller does not work correctly
See points 3.4., 4.7., 4.11., 1.3., 1.4., 5.3., 5.4., 5.7., and 6.
6. The heating conductor
The heating conductor is an important component of the control circuit because it functions both as a
temperature sensor and heating element at the same time. Due to the complexity and variety involved,
the influence of heating conductor geometry is not discussed here. However, some issues concerning
physical and electrical properties will be addressed.
The measurement principle of the resistance temperature controller requires that the heating conductor
has a positive temperature coefficient, which is set at the PIREG-C2. The use of a heating conductor with
a smaller temperature coefficient than that set on the controller can result in the heating conductor getting
overheated or burning up ( 4.7.and 4.11.). Despite full heating capacity, the actual value cannot reach
the target value.
During initial heating of the heating conductor to between 250 and 300 °C, the cold resistance of the heat-
ing conductor varies by 2 - 3 % (burn-in effect). This resistance variation results in a zero-point error of 20
- 30 °C. After a few heating cycles, this zero-point error needs to be corrected by a new calibration.
Overheated or burnt-out heating conductors should not be used because of irreversible changes in the
temperature coefficients.
A constructional measure to improve the exact temperature control and to increase the lifetime of the
heating conductor and the Teflon (PTFE) coating is to copper-plate or silver-plate the heating conductor
contacts. This measure ensures that the heating conductor contacts remain cold and allows the controller
to measure only where sealing is taking place. The temperature of the heating conductor can only be
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