# MKS Instruments 974B Vacuum Pressure Transducer

class pymeasure.instruments.mksinst.mks974b.MKS974B(adapter, name='MKS 974B vacuum pressure transducer', address=253, **kwargs)

  Bases: `MKSInstrument`

  MKS 974B vacuum pressure transducer

  Connection to the device is made through an RS232/RS485 serial connection.

  The 974B pressure transducer is a pressure gauge combining a cold cathode ionization current measurement, a Pirani sensor, and a Piezo sensor to cover a large pressure range. It optionally includes up to three mechanical relays which can be energized based on the measured pressure value.

  Parameters:

    - adapter – pyvisa resource name of the instrument or adapter instance

    - name (string) – The name of the instrument.

    - address – device address included in every message to the instrument (default=253)

    - kwargs – Any valid key-word argument for `Instrument`

  relay_1
    Channel:

      `Relay`

  relay_2
    Channel:

      `Relay`

  relay_3
    Channel:

      `Relay`

  property coldcathode_pressure

    Get Cold Cathode sensor pressure

  property device_type

    Get the device type

  property firmware_version

    Get the firmware version of the instrument

  property hardware_version

    Get the hardware version of the instrument

  id()

    Get the identification of the instrument.

  property manufacturer

    Get the manufacturer name

  property model

    Get the transducer model number

  property operation_hours

    Get the operation hours of the instrument

  property part_number

    Get the transducer part number

  property piezo_pressure

    Get Piezo differential sensor pressure

  property pirani_pressure

    Get MicroPirani sensor pressure

  property pressure

    Get combined pressure reading

  property serial_number

    Get the serial number of the instrument

  property status

    Get transducer status

  property switch_enabled

    Control the user switch to prevent accidental execution of adjustments

  property temperature

    Get the MicroPirani sensor temperature

  property unit

    Control pressure unit used for all pressure readings from the instrument.

    Allowed units are Unit.Torr, Unit.mbar, Unit.Pa.

  property user_tag

    Control the user programmable tag

class pymeasure.instruments.mksinst.mks974b.Relay(parent, id)

  Bases: `RelayChannel`

  property enabled

    Control the assigned input channel or disable the setpoint relay.