TEL AFA1000/BLD, Инструкция по установке и эксплуатации

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Version 01 / p.33
AFA1000/BLD Pressure Controller
Installation & Operating Manual
1. There are various operational setting that need
to be set to give good control of the extract duct
pressure. These setting are adjustable in the
‘Control configure menu’. Due to the possible
variations in the applications each unit will be
supplied with a printed sheet giving the values
of the parameters as set in the factory before
dispatch. (These can also be viewed using a Laptop
computer plugged into the ‘Com port’). The factory
settings are based on previous experience of similar
installations but may require some adjustment to
suit the particular installation.(These setting should
only be adjusted by experienced engineers familiar
with controls and the requirements of the fume
cupboard installations.)
2. Certain parameters can be pre-set from knowledge
of the installation :-
Set point This is the desired extract duct
pressure (during commissioning)
Damper / Inverter For systems with bleed
damper control or variable speed extract fan using
an Inverter
Output range 2-10V or 0-10V depending on
what is being controlled
3. Certain parameters can be adjusted (in small
increments) to improve the stability and
performance of the control :-
Stability: The stability of the system can be effected
by two main items – turbulent airflow across the
face of the pressure sensor or the ‘sensitivity’ of the
control loop. It is important to establish the cause
of the problem before attempting to adjust any
parameters.
To do this put the control system into ‘Manual’
operation and check the stability of the measured
pressure. In this condition the bleed damper or
Inverter will be at a fixed position so any instability
seen will be due to the extract system or to
turbulent air across the sensor. This can be check
and corrected.
If the system is stable in the ‘Manual mode’ the
problem could be due to the control sensitivity
being too high. The sensitivity is set by the ‘Prop
Band’ in the ’Control config menu’. This can be
increased to reduce the sensitivity.
Performance: To reduce the time for the measured
value to go to the set point value ( ie removal of the
‘offset’ ) after a change in duct pressure the ‘Integral
time’ in the ‘Control config menu’ can be increased.
This is normally set to 20 reps/min
4. MIN --- This is a manual fixed position select by the
Night set-back activation and can be adjusted to the
desired value.
MAX -- This is a manual fixed position select by the
Emergency activation and can be adjusted to the
desired value.
Low limit - This is used to limit the travel of the
damper in the opening position or the min speed of
the extract fan to maintain the desired extract rate
from the fume cupboards in normal operation as
the sashes are closed.
High limit - This is used to limit the travel
of the damper in the closing position or
the max speed of the extract fan to maintain the
desired max extract rate from the fume cupboard in
normal operation as the Sash is opened.
Note :- The above information is a guide only
on how to set up and calibrate the controls
incorporating the AFA1000 / E / Bld controller.
7 CONTROL SETTINGS
7.1 Control Settings