Watlow MLS-PM, User Manual

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Overview
MLS User’s Guide 3
Safety
Watlow-Anafaze has made efforts to ensure the reliability and safety of
the MLS™ Controller and to recommend safe usage practices in
systems applications. Please note that, in any application, failures can
occur. These failures may result in full control outputs or other outputs
which may cause damage to or unsafe conditions in the equipment or
process connected to the MLS Controller.
Good engineering practices, electrical codes, and insurance regulations
require that you use independent external safety devices to prevent
potentially dangerous or unsafe conditions. Assume that the Watlow-
Anafaze MLS Controller can fail with outputs full on, outputs full off,
or that other unexpected conditions can occur.
Install high or low temperature protection in systems where an
overtemperature or undertemperature fault condition could present a fire
hazard or other hazard. Failure to install temperature control protection
where a potential hazard exists could result in damage to equipment and
property, and injury to personnel.
The MLS includes a reset circuit that sets the control outputs off or to
the data stored in memory if the microprocessor resets--normally the
result of a power failure and power return. If a memory-based restart
will be unsafe for your process, program the MLS Controller to restart
with outputs off. For additional safety, program the computer or other
host device to automatically reload the desired operating constants or
process values on return of operating power. However, these safety
features do not eliminate the need for external, independent safety
devices in potentially dangerous or unsafe conditions.
Watlow-Anafaze also offers ANASOFT
®
, an optional software
program for IBM-AT
®
or IBM-PC
®
compatible computers. In the
event of a reset, ANASOFT will reload the MLS Controller with the
current values in computer memory. The user must ensure that this reset
will be safe for the process. Again, use of ANASOFT does not eliminate
the need for appropriate external, independent safety devices.
Contact Watlow-Anafaze immediately if you have any questions about
system safety or system operation.