Carbolite CTF Installation, Operation & Maintenance Instructions Manual page 7

Applicable to TZF only.
The TZF is designed to achieve an extended uniform temperature zone by the use of three control
zones. The control zones are typically linked so that they are all follow the central controller in a
master-slave approach; there are two ways of doing this. Alternatively independent control zones
may be ordered. There are thus three control methods (A, B & C).
A. Back-to-Back Thermocouples
This is the most commonly supplied option.
The central zone is controlled directly by the central temperature controller. Each end zone
thermocouple is wired in opposition to a central reference thermocouple, and the small voltage
resulting when the zones are at different temperatures is used by the end zone controller. The
circuit diagram in section 7.2 shows the thermocouple arrangement.
Set the "setpoint" of the end zone controllers to zero.
Sometimes a furnace using this type of control does not cool down: the end controllers try to
remain at the central temperature. Should this occur, contact Carbolite's technical department.
2132 Slave Controller Navigation Diagram
Home
List
0.0
°C/F/k
B. Retransmission of Setpoint
In this system the centre zone controller informs the end-zone controllers of the setpoint that they
are to follow. Additional communication modules are fitted in the controllers, rather than an
additional thermocouple as in A.
It is possible to switch off the master-slave control and allow the controllers to work
independently. On the end-zone controllers, scroll down to
rmt
value from
C. Independent Control
In this case the three controllers are completely independent. Note that it is not possible to
maintain very different zone temperatures because of heat transfer within the work tube.
3.4
MF32
°C/F/k
Zone temperature
difference
Loc
(remote) to (local). There is no need to alter the centre controller.
Access
List
ACCS
home list
Used in factory
codE
configuration; not
accessible to the operator
L-r
and press Up or Down to alter the
1700-1800° Tube
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