Carbon Monoxide Alarm User Manual

Page 36
Note the position of the squared corner. The chip is
designed to fit in only one way.
(8) Reinstall the main board. Reconnect the ribbon
cable connecting the main board to the meter display
board.
Be careful not to crimp any wires as the main board
is reattached.
(9) Reinstall the battery. Make sure all ribbon
connectors are properly attached.
(10) Reassemble the case.
(11) Turn the instrument back on. Verify that all settings
are correct.
Note: If the PhD
2
does not operate normally when
first turned back on, it may be necessary to re-boot
the microprocessor software. Turn the instrument
off and re-boot the microprocessor as discussed in
Section 7.2.1.
(12) Calibrate the instrument before returning to
service!
IC9
IC10
IC8
Software PROM
Figure 7.3. PhD
2
main circuit board showing
placement of the software PROM
Note: If you are upgrading from any Version 3-series
software to any Version 4-series software, a complete
initial setup of the PhD
2
will also be required.
Certain hardware modifications may also be
necessary. Please contact Biosystems for additional
information.
7.4 Replacing the internally housed
(sealed lead acid) rechargeable
battery
Note: Replacement of the sealed lead acid battery
pack requires opening the instrument and replacing
an internally housed component. This procedure
should not be done by unauthorized persons.
To replace the PhD
2
sealed lead acid battery:
(1) Download any recorded data in the instrument
memory prior to replacing the battery.
Disconnection of the battery will result in the loss of
recorded data.
(2) Turn the PhD
2
off.
(3) Remove the five screws holding the instrument case
together and separate the two halves of the case.
(4) Note the position of the sealed lead acid battery pack
and the wires connecting the battery with the main
circuit board.
(5) Carefully pull the battery free of the case.
(6) Disconnect the old battery by gently pulling apart the
two halves of the white nylon four pin connector.
(7) Connect the new battery, and carefully replace in the
instrument case. Do not force! Make sure the wires
connecting the main circuit board and battery pack
are not crimped (they should be tucked underneath
the main circuit board). Check to see that no ribbon
connectors or other components have been disturbed
during the procedure.
(8) Reconnect the two halves of the instrument case.
(9) Calibrate the instrument before putting it back
into service.
7.5 Returning your PhD
2
to
Biosystems for service or repair
Please contact the Biosystems Service Department at
[phone] to obtain a “Return Authorization” number
prior to shipment. A Biosystems Service representative
will record all relevant information or special instructions
at that time.
To insure safe transport please use the original PhD
2
packing materials, or other packing materials which
similarly protect the instrument and accessories.
Note: The return authorization number must be
clearly marked on the outside of the box.
Prominently showing the return authorization number on
the outside of the box ensures that it is immediately
identified and logged into our system at the time it is
received. Proper tracking helps avoid unnecessary
delays in completion of service procedures.
Note: It is usually best to return the instrument together
with all accessories such as spare battery packs,
chargers, and optional sample drawing pumps.
Please contact the Biosystems Service Department if you
require any additional information.
Thank you for choosing the PhD
2
, and thank you for
choosing Biosystems.