Brooks Instrument QMBM - Manual (Page 45)

Section 4 Maintenance
4-5
Installation and Operation Manual
X-CM-QmB-eng
Part Number: 541B029AAG
June, 2011
QmB Series IP40, IP66, IP66XP
Bench Troubleshooting
If it becomes necessary to remove the instrument from the system
after exposure to toxic, pyrophoric, flammable or corrosive
chemicals, purge the instrument thoroughly with a inert fluid such
as water, alcohol, nitrogen, clean dry air or some other appropriate
fluid before disconnecting the fluid connections. Failure to correctly
purge the instrument could result in fire, explosion or death. The
Quantim Mass Flow device may also become corroded or
contaminated upon exposure to air.
WARNING !
Quantim Bench Testing (Refer to Figure 4-1)
1. Establish the proper electrical connection between the Quantim
MFC/MFM. Don not connect the device to a fluid source yet.
a. Connect a +14 Vdc to +27 Vdc power supply to Pin 5 and power
supply common to Pin 9.
b. Connect a voltage output signal read-out device (4-1/2 digit
voltmeter recommended) onto Pin 2 (+) and Pin 10 (common).
c. If applicable, connect current output signal read-out device onto
Pin 4 (+) and Pin 10 (common).
d. Switch on power and allow the instrument to stabilize.
e. In case of a MFC, adjust the setpoint input to zero.
2. Observe the output signal and if necessary, perform the zero
adjustment procedure as outlined in Section 3-2.
a. Only perform the zero operations with the Coriolis Sensor filled
with either 100% fluid or 100% gas at the appropriate pressures
and ensure there is no fluid flowing through the device
(differential pressure = 0 psi).
b. Connect the Quantim to a pressurized supply of inert fluid
(for example high purity water). Fill the Quantim instrument
completely taking care there is no entrained gas in the sensor
and perform the zero operation as described in Section 3-2.
c. When applying Quantim to measure a gas, fill the sensor with
an inert gas (nitrogen or clean dry air) at a pressure near the
process operating pressure.
d. If the output signal does not zero properly, please contact Brooks
Instrument for technical asistance.
3. For a MFC connect a 0-5 Vdc source to Pin 8 and return to Pin 1 or
connect 0-20 mA source to Pin 7 and return to Pin 1.
(See X-CM-Qm-HART-eng instruction manual for complete HART
4-20 mA I/O electrical hookups).
4. Provide an electrical signal to the Quantim representing a setpoint
of 50% of full scale flow and adjust the inlet and outlet pressures to
calibration conditions.