MKS 1253D, Инструкция по эксплуатации

Страница: 55 / 73

Chapter Four: Operation How To Calibrate the 153/1253 Controller
45
Learn the Analog Pressure Zero
1. Warm-up the transducer and pump it below its resolution.
2. Send the Learn Analog Pressure Zero command:
Type Z2, and press ENTER
The 153/1253 controller verifies that the pressure transducer is properly warmed-up and
pumped below its resolution. The 153/1253 learns the pressure input that corresponds to
the analog pressure zero value. The analog pressure zero value is factory set to 0.0 Volts.
Learn the Analog Pressure Full Scale
1. Warm-up the transducer and set up the pressure system for full scale pressure.
Before you issue this command, be sure that the input voltage is at least 9% of the 10 V
full scale voltage. If the voltage is less than 9% of the typical full scale voltage, the
153/1253 controller ignores the learn command and retains the previous value. This
eliminates the possibility of learning an erroneous voltage value.
2. Send the Learn Analog Pressure Full Scale command:
Type F2, and press ENTER
The 153/1253 controller raises the pressure to the full scale value of the transducer. The
153/1253 learns the pressure input that corresponds to the analog pressure full scale
value. The analog pressure full scale value is factory set to +10.0 Volts.
Learn the Number of Valve Steps
•
Send the Learn Number of Valve Steps command:
Type V and press ENTER
The 153/1253 controller opens and closes the valve, so be sure that it will not affect your
system. Factory set for the attached valve.
How the 153/1253 Controller Handles the Calibration Voltages
When a voltage enters the 153/1253 controller as a calibration signal, for a pressure full scale or
pressure zero reading, the controller scales the signal to allow for a slightly overrange or
underrange signal. The controller does not convert the signal back to a full 0 to 10 V range.
Therefore, when you query the controller for a pressure zero or pressure full scale reading, it will
return the offset value, rather than the true zero or full scale voltage reading.