Graseby 3000/500, Manual

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G r a s e b y M e d i c a l L t d .
8 — 8 I s s u e A ( A p r i l 2 0 0 2 ) 3 0 0 0 / 3 1 0 0 a n d 5 0 0 / 5 0 5 S e r v i c e M a n u a l
V o l u m e t r i c I n f u s i o n P u m p s
8
Membrane switch replacement
The Membrane switch consists of two parts; the lower electronic
switch, and the upper overlay and keypad graphics. Once in place on
the door assembly the two parts are removed as a single unit. The
original membrane switch must not be reinstalled because electrical
damage during removal could have occured.
The door must be disassembled (see above) in order to replace the
membrane switch. With the door assembly open, remove the ribbon
connector from P403 on the Display board, then remove the Display
board. On the front of the door, peel up and discard old membrane
switch. Clean any residual adhesive from the housing.
Follow this procedure to replace the membrane switch:
1. Peel the release liner from the back of the electronic switch (front
of membrane switch has raised domes). The release liner on the
front of the switch must not be removed at this time.
2. Thread the ribbon cable through the slot provided on the door
front.
3. Apply the membrane switch to the door front and press it firmly
into place using the fingers. Avoid excess pressure on the actual
domes.
4. Once the electrical switch is firmly in place, remove the release
liner from its front. Also, remove the release liner from the back of
the graphics overlay.
5. Place the graphics overlay over the electrical switch, making sure
to line it up correctly with the electrical switch portion. Press
firmly around the outer edges, around the display windows, and
vertically between the rows of numbers. Avoid excessive pressure
on individual keys.
6. Connect the ribbon cable to P403 on the back of the display board.
Press board firmly into the board retainers.
Reassemble the door. Perform the functional and accuracy check. If
the check is satisfactory, complete the Housing reassembly.
WARNING: Unplug the AC power cord before opening the pump housing to avoid risk of electric
shock, which could result in death or serious injury.
CAUTION: Disconnect the battery connection P104 on I/O board before disassembling the circuit
boards to avoid circuit damage. After disconnecting P104, press the
On/Off key twice to
discharge the circuitry.
CAUTION: Handling of printed circuit boards is required during disassembly/assembly. A static
controlled work station including a conductive mat and grounded wrist strap should be
used to provide protection against electrostatic discharge (ESD) or circuit board damage
could result.
(Original case design)