www.globalplasmasolutions.com
© 2022 GPS Air
GPS Air is the owner of certain trademarks that appear in our materials. Please visit www.gpsair.com/trademarks for a list of our marks.
www.gpsair.com
Scale Selection
The scale on which the ions are read can be adjusted. To adjust the range (sensitivity) of the
GPS-iMEASURE-D, move the white jumper on the control board. See FIGURE 2 and FIGURE 3.
• No Jumper = 10k ions/cc/sec (0V = 0 ions and 10V = 10k ions)
• Jumper on center and right pin position “A” = 100,000 ions/cc/sec (0V = 0 ions; 10V = 100k ions)
• Jumper on left and center pin position “B” = 1,000,000 ions (0V = 0 ions; 10V = 1M ions)
Programming Note: If you don’t know what
scale to use, start with the 10k ions/cc/sec scale.
If the output voltage stays near 10V on this
scale, move the jumper to read 100k ions/cc.
If the output voltage stays near 10V on this
scale, move the jumper to read maximum
level of 1M ions/cc/sec.
Initial Power Up
Once power is applied, the GPS-iMEASURE-D will go through a 15 second calibration cycle.
During this time the LED will flash red or green (depending on detection polarity) and, the
output will go to 0VDC. The bi-color LED will be solid red or green when power is applied
and there are no faults.
Self-Test
Upon power up and once every hour the GPS-iMEASURE-D will perform a self-test. During the
self-test the device’s ion sensitivity is tested. During the self-test the output levels are held at
the pre-auto zero level. Upon a fault, the LED will flash alternating red and green, and the
output level will be pegged at 10V (remote indication of error). The most common cause of an
error is the sensor is grounded in more than 1 location.
Indicators
• Dual color LED
• Blinking Green: Positive polarity self-test
• Solid Green: Positive polarity normal operation
• Blinking Red: Negative polarity self-test
• Solid Red: Negative polarity normal operation
• Alternating Green and Red: Self-test failure
Maintenance
Accumulation of lint and dust, spider webs or web fragments within the ion chamber can cause
inaccurate readings, the inability to auto-zero or the ability to maintain a proper chamber
voltage. This can usually be corrected by cleaning the chamber with canned compressed air.
It is advisable to periodically blow out the chamber with compressed air. The frequency of this
preventative procedure will depend on the environment in which it is used. Cleaning the unit/
chamber once a year will usually be sufficient in non-industrial environments.
Figure 2
Figure 3
Jumper
