4230 Flow Meter
Section 5 Maintenance and Service
5-11
The flow meter will revert to the program originally entered at
the factory. If this operation is performed, it will be necessary for
you to reprogram the unit to meet the specifications of your
installation. For this reason, it may be a good idea to keep a
record of how you programmed the unit. The Print Program
feature will do that for you.
Pressing 4 and Exit Program may leave some values pro-
grammed into the flow meter's computer. If you want to remove
all programmed entries, press 1 and Clear Entry when the flow
meter is powering up.
The following messages describe serious internal problems, indi-
cating service is required:
ROM CHECKSUM ERROR - or -
FOUND BAD RAM - CALL CUSTOMER SERVICE
If these messages appear, the Isco Technical Repair Department
should be called for instructions at (800) 775-2695 or (402)
464-0231.
CAUTION
Do not attempt to disassemble or repair the 4230 Flow Meter
(other than changing fuses) unless you are skilled in the evalu-
ation and repair of microprocessor-based circuitry. Isco recom-
mends no attempt be made to disassemble or repair the
printer mechanism or display module.
5.7 Operation of the
Bubbler System
This system produces the pressurized air supply for the bubbler,
regulates the rate of air to the bubbler tube, measures the
pressure in the bubbler tube, does purge, drift compensation, and
other functions.
5.7.1 Internal Air Pump A small, high-efficiency pump generates the pressurized air
supply for the bubbler. The suction side of the pump connects to
the outside of the case through the pump inlet port barbed hose
connector. This vent is separate from the other components to
prevent interference from the pumping cycles. The exhaust side
of the pump connects to the air supply tank, which is pressurized
by the pump.
To Next Page
Loading...
