MKS 651D Series, User Manual, Page: 75 / 162

Chapter Four: Local Operation Operation
63
How To Remove the Zero Correction Factors
This function removes the sensor and special zero correction factors stored in memory, and is
used to determine the uncorrected signal from the pressure transducer. Each time a sensor is
zeroed, the offset changes and the pressure display is updated. In some applications it may be
important to keep the zero offset within a specific range.
To remove the zero corrections:
1. Press the [S
TOP
] key and the [Z
ERO
] key simultaneously for about three seconds
until the front panel display changes from a zero pressure reading to the uncorrected
signal level.
2. Press the [STOP] key to return to the default Pressure and Position display screen.
How To Zero the Analog Set Point
This function instructs the controller to take the current value of the external analog set point for
its zero value. Zeroing the analog set point allows you to correct any controller zero offsets.
To zero the analog set point:
1. Apply zero input voltage to Interface connector pins 33 and 34.
Note
Pin 34 should be connected to Pin 35 to properly ground the analog
input.
Refer to Table 8, for the Interface connector pinout.
2. Press the [ ] and [S
TOP
] keys simultaneously for about three seconds.
The screen displays:
CAUTION
CALIBRATION MODE
3. Press the [S
ETPOINT
B] key.
The screen displays:
ANLG SP: 100.00 %
LEARN+ZERO to CAL