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Pressure Zero Adjustment Chapter Seven: Maintenance
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DeviceNet Zeroing Commands
The MFC must be in the executing state then send the zero service with a target value of zero. The following
assumes explicit messaging only using the DeviceNet communication protocol.
Place the device in the Executing State through the S-Device Supervisor Object: Note the response Status:
Success
The following DeviceNet Command places the device in executing.
Service 0x06, Class 0x30, Instance 1
1) Verify you are in executing through the S-Device Supervisor Object: Note the response Data (hex): 04
means we are in executing. Attribute 0x0B The following DeviceNet Command is used to verify you are
in executing.
Service 0xE, Class 0x30, Instance 1, Service Data (attribute) 0x0B
You should get response data of 0x04
2) Send the Zero Adjust Service using S-Analog Sensor Object Instance 2 (Pressure)
The following DeviceNet Command Starts the Pressure zero.
Service 0x4B, Class 0x31, Instance 2, Service Data (Target Value) can be Empty Data or Data Type
based value, i.e. 2 byte for integer or 4 byte real value, if a value is used, it must be a target value equal
to zero.
3) The pressure zeroing procedure usually takes several seconds to perform. Recheck your pressure to verify
zero has occurred. You can also perform an explicit GET(Service 0x0E) on Class 0x31, Instance 2,
Attribute 0x1C, which is the Autozero Status. This attribute’s service data will equal “1” while zeroing is
in progress and equal “0” when the zeroing has completed. It is most important that the device is at a zero
pressure, if a high pressure is detected by the MFC, then zeroing will not occur.