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2.SS – Start Source:
a) The compressor will start using the start key.
b) The compressor will start using a remote RS 485 communication. The start key will be disabled.
The compressors are equipped by the manufacturer with the pressure sensor mode. The pressure switch mode may be used in
times when the pressure sensor needs any maintenance and the compressor cannot stop working.
Under this working mode, the high pressure alarm and the overpressure protection are ignored.
2.Po/2.Pr - Pressure sensor mode (Standard System):
The interface is designed for using a pressure sensor with a 4-20mA signal, and which may work with a feeding voltage as low as 16Vdc.
The sensor “range” and settings may be adjusted using the “Po” (offset) and “Pr” (range) parameters. The standard values for Schulz
compressors are 0-16 bar (0-232 psi).
The polarity of the cables is important.
Procedures for the calibration of the pressure sensor:
a) Expose the pressure sensor to atmospheric pressure (0.0 bar, relative). Set “Po” offset value until the pressure displayed is 0.0 bar.
b) Apply a known precise pressure to the sensor. The pressure may be static or dynamic (variable). Set the “Pr” range value until the
pressure displayed is equal to the pressure applied. The pressure applied may have any value, but it is recommended that the pressure be
at least equal to the compressor’s working pressure
The pressure detected by the sensor is displayed when the “Po” and “Pr” parameters are selected to make the adjustment easier.
2.tL – Minimum temperature (load)
If the measured temperature is below the minimum temperature (load), and the compressor is ordered to enter load, the interface will not
allow the compressor to do so; it will remain in relief, until the temperature increases to values above the minimum temperature (load).
When this condition occurs, the interface will show the A3423 Err Alarm. The alarm will be automatically eliminated when the temperatu-
re exceeds the minimum temperature (load). This alarm cannot be manually eliminated.
To disable this function, set value to 0 (zero).
