Setra System Model 470 - Manual (Page 25)

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8. Transmit C, for CLEAR.
9. The Setra 470 next reports the VERIFY message described in Section 5.7 and executes
the internal start-up procedure for thirty seconds. When the start-up procedure is complete,
the transducer again reports VERIFY message. It is not possible to interrogate or perform
any other function with the Setra 470 before you receive the second VERIFY message.
5.6 Software Revision Number
The Setra 470 internal software is stored internally in a PROM (Programmable Read Only
Memory). From time to time, Setra may revise or update the software. Use the following proce-
dure to obtain the revision number of the software in your 470.
1. Use the CONVERT function (see Section 4.2) so that the 470 reports data in units of
pressure in response to an interrogation. (i.e., the transducer should not be reporting in units
of altitude.)
2. Transmit -7777S. This is the software Revision access code.
3. The transducer responds “REF” followed by the revision number of the transducer
software.
This manual is correct for version 2.0 software.
5.7 Verify Function
The Setra 470 transmits a test message to verify that the bidirectional communications are
working and to identify the pressure range of the unit. Use the following procedure to verify
communications and identify the unit.
1. Use the CONVERT function (see Section 4.2) so that the 470 reports data in units of
pressure in response to an interrogation. (i.e., the transducer should not be reporting in units
of altitude.)
2. Transmit V, for VERIFY.
3. The 470 responds with a message like the one shown below. The pressure range
reported differs depending on which range transducer you are working with.
SETRA DIGITAL PRESSURE TRANSDUCER
MODEL 470
11.0000 TO 16.0000 PSI A
5.8 Stability Indicator
The Setra 470 can monitor the stability of the pressure being applied to the sensor. The “OK”
symbol is reported whenever the pressure is changing by less than the Stability Indicator Limit
amount from one reading to the next.
The Stability Indicator Limit is used when the Setra 470 is serving as a Secondary Pressure
Standard, to ensure that calibration pressures being applied to another device are accurate and
stable within a given limit. For example, to indicate whether a pressure of 15 PSI is stable to
within
±
.001 PSI, the Stability Indicator Limit would be set to .001 PSI. On power-up, the Stability
Indicator is set to the factory default (usually 1.5 times the resolution of the display). Any Stability
indicator parameter entered by the user before power-down is not retained on power-up.