Carrier 30RB-170R, Инструкции по установке, эксплуатации и обслуживанию

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Procedure for controlling the pressure differential setpoint
Once the circuit is cleaned, place the hydraulic circuit in the
configuration for which the unit selection was performed (generally,
this will be all valves open and all cooling coils active)
Read the flow rate on the user interface and compare the value
obtained with the theoretical value of the selection:
- If the flow rate read is greater than the preset value, reduce
the pressure differential setpoint on the user interface to
reduce the flow rate value;
- If the flow rate read is lower than the preset value, increase
the pressure differential setpoint on the user interface to
increase the flow rate value
Repeat until the unit's nominal flow rate at the required operation
point is achieved.
Stop the forced operation of the pump and proceed to the
configuration of the unit for the required control mode. Modify the
control parameters:
- Set water flow rate control to “pressure differential”
- Set the value of the required pressure differential.
The unit's default factory configuration is the minimum speed
(frequency: 30 Hz).
NOTE:
If during adjustment, the low or high frequency limits are
reached before reaching the specified flow rate, keep the
pressure differential value at its lower or higher limit as the
control parameter value.
If the user knows in advance the pressure differential value
at the unit outlet to be maintained, this value can be entered
directly as a parameter to be declared. You should not,
however, omit the hydraulic circuit cleaning sequence
9.4 - Units with hydraulic module and variable-
speed pump – Temperature differential control
The installation flow rate has not been set to a rated value.
The flow rate will be adjusted, by varying the pump speed,
to maintain a heat exchanger temperature differential value defined
by the user.
This is checked by the temperature sensors at the water exchanger
inlet and outlet (items 8 and 9 on the typical hydraulic circuit
diagram).
The system reads the measured temperature values, calculates
the corresponding Delta T°, compares it with the setpoint value
set by the user and then modulates the pump speed accordingly.
- This results in an increase in the flow rate if the Delta T
exceeds the setpoint.
- This results in a decrease in the flow rate if the Delta T is less
than the setpoint.
This variation in flow rate is limited by the maximum and minimum
permissible flow rate values for the unit and by the maximum and
minimum pump supply frequency values.
The maintained Delta T may, in certain cases, differ from the
setpoint value:
- If the setpoint value is too high (corresponding to a flow rate
lower than the minimum value or a frequency less than the
minimum value), the system will be limited to the minimum
flow rate or minimum frequency, which will result in a
Delta T below the setpoint,
- If the setpoint value is too low (corresponding to a flow rate
higher than the maximum value or a frequency greater than
the maximum value), the system will be limited to the
maximum flow rate or maximum frequency, which will result
in a Delta T above the setpoint.
Contact the manufacturer's Service to implement the procedures
described below.
Hydraulic circuit cleaning procedure
Refer to the hydraulic circuit cleaning procedure.
Procedure for adjusting the Delta T setpoint
Once the circuit is cleaned, stop the forced operation of the pump
and proceed to the configuration of the unit for the required control
mode.
Modify the control parameters:
- Water flow rate control method (temperature differential)
-Set the required Delta T.
The unit's default factory configuration is the minimum speed
(frequency: 30 Hz).
9.5 - Units with hydraulic module and variable-
speed pump - Setting a fixed flow rate for the
system
The flow will be set to a nominal value. This value will remain
constant, and will not be dependent on variations in the
installation's load.
Contact the manufacturer's service department to implement the
procedures described below
Hydraulic circuit cleaning procedure
Refer to the hydraulic circuit cleaning procedure.
Procedure for controlling the flow rate
Once the circuit has been cleaned, set the required water flow
rate by adjusting the pump frequency on the user interface.
Stop the forced operation of the pump and proceed to the
configuration of the unit for the required control mode. Modify the
control parameters:
- Water flow rate control method (fixed speed)
-Constant frequency value.
The unit's default factory configuration is the minimum speed
(frequency: 30 Hz).
9 - NOMINAL SYSTEM WATER FLOW RATE CONTROL
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