Trane RTUD, Установка, эксплуатация и обслуживание

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RLC-SVX14H-GB
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External Analog Output
As an option, CH530 provides a 2-10 VDC analog output
to indicate condenser pressure. The confi guration item
provides for the installation of the necessary hardware
and software as well as defi nes which of two possible
ways the output is confi gured. The selections for the
confi guration item are as follows:
1) Analog voltage output is a function of percent HPC
condenser pressure - Percent HPC Condenser Pressure
Indication
The transfer function is 2 to 10 Vdc corresponding to
0 Psia (or kPa abs) and the Software High Pressure
Cutout (HPC) setting in Psia (or kPa abs). The Percent
HPC Condenser Pressure indication output is based on
the Condenser Refrigerant Pressure transducers.
Note: For the RTWD and RTUD chillers, the High
Pressure Cutout Setting is replaced by the Software
High Pressure Cutout setting, (The Software HPC is
a confi guration setting and is defi ned as an absolute
pressure (its inherent units is Kpa (abs)). For multiple
circuit chillers, such as RTWD, the condenser pressure
used in the calculation will be the lowest condenser
pressure of all of the running circuits. Condenser
pressure transducers that are invalid (i.e. non-
communicative or out of range) will be excluded. Note:
If both transducers are invalid, then output shall 1.0
VDC (per the table below), but if only one is invalid, the
opposite transducers value shall be used for the analog
output.
For this feature:
Percent HPC = ((Lowest Condenser Pressure of all
running circuits (abs) / Software HPC confi guration
setting in absolute units*100.
The following equations are applied:
Percent HPC
Percent HPC Condenser
Pressure Indication
Output(Vdc)
Sensor (or all sensors)
out of range
Vdc = 1.0
0-100 Vdc = .08(Percent HPC)+2
>100 Vdc=10.0
Communications Interface options