User Manual

Page 20 Part # 68C-MKU, Edition 01/2007, Version 1.0
Redundant Self-Checking Dual Processor Architecture:
Both the OCU and the MCU incorporate one Master processor and one Slave (checker)
processor. On the OCU, these dual processors monitor the output commands from the
pushbuttons. On the MCU, these dual processors monitor the input commands to the relay
coils.
3.2 PERMANENT OCU ‘TRANSKEY’
When the ‘TransKey’ is removed, the OCU is totally disabled. Thus, the ability to remove the
TransKey from the OCU is an important safety feature that prevents unauthorized operation of
the controller and its target machinery.
A Permanent ‘TransKey’ Retainer ia also supplied with your OCU. Installing this item as
shown in Figure 6 below will securely retain the TransKey within the OCU’s top end cap.
CATTRON
®
strongly emphasizes that installing the Permanent ‘TransKey’ Retainer is entirely
at the operator’s discretion. An operator should be aware that securely retaining the
‘TransKey’ within the OCU’s top end cap will not prevent unauthorized operation of the
controller or its target machinery.
THEREFORE, WHEN NOT IN AUTHORIZED USE, CATTRON
®
RECOMMEND THAT A OCU
HAVING A PERMANENTLY RETAINED ‘TransKey’ BE HELD IN A SUITABLE CABINET
UNDER LOCK AND KEY.
Figure 6. Permanent and Removable ‘TransKey’ Retainers