BRONKHORST CORI-TECH B.V.
3.4 Start-up
Turn on fluid supply gently. Avoid pressure shocks, and bring the instrument gradually up to the level of the
actual operating conditions. Also switch off fluid supply gently.
3.5 Operating conditions
Each instrument has been calibrated and adjusted for customer process conditions.
Controllers or valves may not operate correctly, if process conditions vary too much, because of the
restriction of the orifice in the valve.
3.6 Instrument performance
3.6.1 Meters
Each meter has a step-response of about 50ms. The special adaptive filtering technique in the CORI-FLOW
detects that the flow is changing rapidly and will decrease filtering immediately so a fast response is
possible. After the flow change the filter will increase to get a steady signal.
3.6.2 Controllers
The dynamic response of a controller is factory set. Standard settling-time is defined as the time to reach the
setpoint (and stay) within
±
2% of the initial setpoint. The settling time depends on the properties of the flow,
the system pressure and the valve type used. It can vary between 500ms and 3 seconds.
The control mode is factory set in such a way that after a stepwise change in the flow, there will be little
overshoot.
3.7 Manual operation
By means of manual operation of the push-button switch (#) some important actions for the instrument can
be selected/started. These options are available in both analog and BUS/digital operation modes.
(See also manual operation in document number 9.17.023)
These functions are:
- Reset (instrument firmware-program reset)
- Zeroing
- Restore factory settings (in case of unintentionally change of the settings)
for FLOW-BUS only:
- Automatic installation to FLOW-BUS (installs instrument to free address)
- Remote installation to FLOW-BUS (instruments will be installed by E-7000 or PC-software)
3.8 Analog operation
Digital
instruments can be operated with analog signals through the 8-pin circular connector. The
instruments are compatible in use with
analog
instruments on this point.
Analog operated instruments, can be hooked up using an 8-wire shielded cable, connected according to the
Bronkhorst Cori-Tech standard.
Each electronic P. C. board is set for one of the following output (and corresponding input) signals:
Signal
output (sensor)
input (setpoint)
code
signal
signal
A
0…5 Vdc
0…5 Vdc
B
0…10 Vdc
0…10 Vdc
F
0…20 mA (sourcing)
0…20 mA (sinking)
G
4…20 mA (sourcing)
4…20 mA (sinking)
9.17.031
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