Precision, Performance, Confidence. ™

6270A/8270A in Dual Role as DUT and AutoGEN Controller

Alternate Title:  Calibrating a 6270A AutoGEN controller using COMPASS for Pressure.



When used with a PG7000 piston gauge the 6270A / 8270A / 8370A series of pressure controllers are typically used to automate the piston floating process.  In this role they are an extension of the PG7000 and are not visible to the COMPASS software.  If the 6270A is to be calibrated, then automated data collection can be enabled in COMPASS to read the output of the 6270A.  It is important to distinguish that the fully automated  “In-Chassis Calibration”  method is not possible when the 6270A is configured to be the AutoGEN controller.  This tutorial addresses how to automate the measurement collection from the 6270A while it simultaneously functions as the AutoGEN controller.


Define a Non-AutoDetect DUT Definition:

This 6270A is to be used as the DUT.  Its output is queried via the PG's COM3 port using the PPCPR command.  In many situations it simplifies the operations if all other modules not being calibrated are removed from chassis.  The exception to this is the PM230 or PM630 high pressure module used with the 8370A.  For this application, the PMM to be calibrated must first be made "fixed" from the 8370A front panel.   A separate DUT Definition is encouraged to be used for each PMM to be calibrated.



The Remote Communications between the 6270A and COMPASS (the host computer) is via the PG7601.  Therefore the 6270A definition must be configured to use the same RS232 port and settings as the PG7601.  This goes against traditional RS232 rules and it will trigger a warning message at the end of the test initialization sequence, but it can be acknowledged and COMPASS will proceed with starting the test.  In this screen shot the PG7601 is connected to the host computer using the COM8 port.  Therefore the 6270A must also use the COM8 port.


Global Settings Tab – the use of the Poll Frequency delay is critical to allowing the proper interrupts on the serial communications between the PG and COMPASS:


Make a dedicated Output for each PMM:



This is the warning message that both devices are using the same COM port.  Click OK to acknowledge and proceed.


Have more questions? Submit a request


  • Avatar
    Mehmet Demirel

    Thanks, very good and very easy primary standard we have a PG7202 AMH 100, thanks Matt Daniels

    Comment actions Permalink

Please sign in to leave a comment.