System Description; Operation; General; Warm Up And Leak Check - Hartridge HM1023 Operating And Servicing Manual

HARTRIDGE LIMITED

3. System Description

The AE72 Audit Test Box provides a 5 Volt supply to a high pressure transducer. The voltage is
derived from the 9V battery. The transducer provides a ratiometric output voltage (between 10 –
90% of supply voltage), the output voltage is proportional to the applied pressure, where 0.5V is
equivalent to zero bar and 4.5V is equivalent to 2800 bar.
The AE72 Audit Test Box is calibrated to convert the transducer output voltage into a displayed
pressure. The AE72 Audit Test Box has two modes:-
 CAL
Provides a reading of the 5V supply voltage to the transducer. The pressure reading is
dependent on an accurate supply voltage. It is important to periodically check the 'CAL' value
is within tolerance to ensure accurate readings.
 Overcheck
Provides a reading of the applied pressure. With the paired transducer connected, but no
pressure applied, the reading should be zero.
The Pressure Transducer (PTD) Simulator provides a means of checking the calibration of the host
machine. A switch connects a simulated 0 bar or Maximum 2800 bar signal into the system. The
PTD Simulator connects to the AE72 Audit Test Box via the adaptor cable A281P201, provided in
the kit.

4. Operation

4.1 General

The following sections describe typical procedures for the use of the AE72 Pressure Audit Kit. In all
cases the correct audit process for the host machine must be followed.
Certificates of Compliance must be completed to confirm the host machine is within tolerance.

4.2 Warm Up and Leak Check

WARNING! HIGH PRESSURE FLUID SPRAYS CAN CAUSE SERIOUS INJURY OR
DEATH.
COMMON RAIL SYSTEMS OPERATE AT EXTREMELY HIGH PRESSURES.
ENSURE THAT ALL PANELS ARE FITTED TO THE HOST MACHINE.
1. Set up the host machine to run a test, using injectors capable of high pressures.
2. If a 4 line CRi-PC is used, ensure that unused injector positions are populated with injectors but
do not connect the injector control cable to the unused injectors.
3. On any host machine, ensure that unused connectors are stowed away to prevent damage to
them.
4. Start the host machine in Manual Mode, to allow control of rail pressure and injector parameters.
5. Set the rail pressure to 400 bar and check for leaks around the pressure transducer connections.
If a leak is present, stop the machine, ensure the rail pressure has been relieved, switch off the
machine and fix the leak.
6. When there are no visible leaks, run the host machine at approximately 1000 bar. Run for
several minutes to allow the system to purge air and the temperature to stabilise. Recheck for
leaks.
HL078 (EN), Issue 1, AT3376, 04/2018
HM1023 (AE72) Operating and Servicing Manual
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