September 2007 Edition
Structure and Function
epm
Page 3-16
Operating Manual CIG compact TMS Duplex Automatic Soldering Machine
3.5.4 Heating
System
3.5.4.1 Main
System
The heating system consists of a heater set of 6 elements immersed in solder. The heaters
are controlled proportionally by means of triacs, as a result of which, in combination with
the direct contact between the heater and the solder, a very high temperature stability of
the solder is reached. The heating elements are so constructed that together with the addi-
tional heating, solder explosions are avoided.
When using a solder with an eutectic melting point, the copper enrichment of the solder
bath must be taken into consideration. The melting point of the solder increases with an in-
crease in the copper enrichments, which reach the solder bath from the PCB tracks and the
component leads; the solder loses its eutectic melting point. Depending on the copper
quantity that has been drawn in, the melting point of the solder can increase from 183°C to
about 215°C.
The solder temperature is freely programmable from 235°C to 295°C. The solder tempera-
ture is under closed-loop regulation with a temperature tolerance of
±
1°C; the target value
and the actual temperature are displayed digitally. The temperature-dependent 220 V-
circuit is automatically connected and releases the machine as soon as the set temperature
has been reached and 40 minutes of after-running time have elapsed. In case of overheat-
ing from a malfunction, the heating system is automatically switched off at 300°C.
3.5.4.2 Auxiliary
System
Two additional anti-explosion-heaters (additional heating), that melt the solder at the sur-
face, create an escape zone for the overpressure, which results from the melting of the sol-
der under the hard surface, and for those gases that result owing to pollution of the solder
bath.
