Honeywell 900U02-0100 - Table 36 - Power Supply Replacement (All Except C75)

212 ControlEdge HC900 Process & Safety Controller User and Installation Manual Revision 10
May 2019
EXPLOSION HAZARD Class 1, Division 2 Installations
 SUBSTITUTION OF COMPONENTS MAY IMPAIR SUITABILITY FOR CLASS i, DIVISION 2.
EXPLOSION HAZARD Class 1, Division 2 Installations
 Do not DISCONNECT EQUIPMENT UNLESS POWER HAS BEEN SWITCHED OFF OR THE
AREA IS known not to BE HAZARDOUS.
Replacing the Power Supply
The power supply for the ControlEdge HC900 Controller is available in two models and is used in the
local (controller) rack and in the remote (I/O expansion) racks, in 4-, 8-, and 12-module sizes. This
reduces required inventories of spare parts, and also simplifies removal and replacement procedures.
Removing the power supply from a rack will remove all DC voltages from the rack that powers the
Controller Module or Scanner Module, and from all I/O modules within the rack.
NOTE:
The power supply includes an internal fuse, rated at 5 amperes. This fuse is not replaceable in the field.
If desired, the user can provide an external fuse that has a current rating lower than that of the internal
fuse. See page 75.
Table 36 – Power Supply Replacement (all except C75)
Step
Action
1.
ATTENTION: This procedure does not apply to C75 power supplies.
If the power supply to be replaced is powering a rack that is currently controlling a running
process, then:
Either:
 Ensure that powering the rack down will not have adverse consequences on any running
process.
Or:
 Bring the process to a safe and orderly shutdown.
2.
Using an external, user-supplied switch, disconnect the power supply from the source of site AC
power. Use a meter to ensure that power is off.
3.
Depending on the type of wire lugs used, loosen or remove the three screws on the terminal
board, and remove the three wires from the terminal board.
NOTE: DO NOT remove the nut that secures the lug for the PE Ground wire (green) to the
grounding stake at the bottom of the rack.
4.
At the top and bottom of the module, loosen the captured screws that secure the module in the
rack, and remove the power supply from the rack.
5.
Place the new power supply in the rack. (cont’d)
6.
Secure the lugs for AC wiring to the terminals on the new power supply.
 L1 (top terminal) - Black (USA) or Brown (Europe)
 L2 /N (middle terminal - White (USA) or Blue (Europe).
 Ground (bottom terminal)
7.
Ensure power can be applied safely, and use the external (user-supplied) switch to re-connect
power to the power supply.
8.
Using a meter and the test points on the face of the power supply, ensure that voltages (measured
on the backplane) are within specifications.