Centron Technologies MS930A, Service Manual

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The control unit contains power supplies, RF generator boards and control circuit board.
Each power supply unit supplies 12 volts DC current to each RF generator board that
generates 40.68 MHz RF power. RF powers go to the segmentation unit through coaxial
cables in the inter-unit cable assembly.
The power switch
(3)
is located on the rear panel. When it is turned on, the POWER ON
lamp
(1)
lights. The power switch module contains a recoverable circuit breaker that trips
off when an over-current condition occurs in the system. There is no other control on the
control unit.
Connections with the segmentation unit are made from rear panel. An end of each cable in
inter-unit cable assembly is plugged at RF OUT connectors
(5)
and data cable connector
(6)
.
Remote control connector
(7)
is used only when the machine is operating in remote mode.
A cycle of sealing process starts by a signal from the segmentation unit given through the
inter-unit cable, or by a signal from a remote control device connected at the remote
control connector. The control unit feeds RF powers to all sealing head units for a
determined period of time, as well as it controls movement of each sealing head.
The sealing counter
(2)
counts up by 1 at each one cycle of sealing process.
Upon receiving start signal, the sealing heads start not at same time but one by one in
series. Time interval between start of one sealing head and start of the next sealing head
can be selected between 60-160 milliseconds with 20 milliseconds step.
Operation sequence of sealing heads can be also selected, to start them from the right head
to the left head, or from the left head to the right head.
Return timing of sealing heads can be selected too. Each sealing head can be returned
individually at the moment when sealing ends at that sealing head unit, or all sealing
heads can be returned simultaneously when the last working sealing head ends its job.
Each sealing head can be enabled or disabled individually by switches on the control
circuit board, as well as by software command if the machine works in remote mode.
Default factory settings and adjustment procedures are found in Section 5-2.
The machine operates in one of four operation modes: local, remote switch, remote circuit
and remote command modes. Power-on default is local mode if no connector is connected
on the remote control connector. Details are found in Section 4.
When sealing is not made at a sealing head, audible and visual alarms are activated. Alarm
condition is set up when any sealing head has not made seal in 3 seconds from start due to
circuit failure. Alarm continues until the trigger lever at #1 sealing head is released by
removing tubing.