HC900 Hybrid Controller Installation and User Guide

Removal and Replacement Procedures - Overview
Revision 5 HC900 Hybrid Controller Installation and User Guide 145
9/03
Removal and Replacement Procedures
Overview
This section contains procedures for removing and replacing the active components of an HC900 Hybrid
Controller. It also includes recommendations, suggestions, and hints as they apply to the circumstances
under which the procedures are used.
Safety Considerations - PLAN AHEAD!
When using the procedures in this section, plan the sequence of procedural actions so as to ensure:
• The safety of personnel
• The protection of property
• The integrity of operating processes
The first consideration is safety of personnel. While there is always an inclination to preserve the
materials and time invested in a running process, no action should ever be taken that would risk
injury to personnel.
Protection of personnel property is an important consideration that always requires comprehensive
knowledge of the entire control process: the control equipment, the process control strategy, and the
conditions and circumstances that exist when the removal and replacement procedures are taken.
The procedures in this section include notices of potential hazard as they apply to various components in
the controller. Because each control process and the set of conditions and circumstances at each user site
are unique, it is the user's responsibility to know the potential consequences of each action as it relates to a
running process.
It is recommended that the user becomes familiar with the significant aspects of each set of circumstances
and has a plan for execution of the proper action sequence.
All of the input/output modules available for use in the HC900 Controller have a RIUP designation. That is, they can
be Removed and Inserted Under Power, where "power" refers to DC power at the backplane of the rack. (It does
not refer to power for field wiring at the terminal board associated with the I/O module, which must be disconnected
(using a user-supplied switch) at the field device before removing or inserting the module.
For all other components of the controller, AC power to the controller must be removed before removal or
replacement of the component.
Hazardous voltages exist at the Power Supply and at the terminal boards on I/O Modules
• Only trained and authorized personnel should perform the procedures in this section.
• Disconnect all sources of power associated with these components before removal or insertion.
Failure to comply with these instructions could result in death or serious injury.