ProMinent ProMix C, Operating Instructions Manual

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Pr o Minent ProMix
‘S & C’ Polymer Feeder
ProMix Series S&C User Manual
2.9 Scale the 4-20mA Input (continued)
Press ENTER @ 4-20mA Input
to calibrate the 4-20mA current loop input
from the site’s control system.
Press UP or DOWN to the Scale lin @20mA display
& then press ENTER .
Press RIGHT to move the underline cursor &
UP or DOWN to modify the value @ the cursor.
Press EXIT to leave the present setting unchanged.
You can modify either or both of the mA level and the
resulting pump feed %.
Press ENTER when finished editing.
Displays new, adjusted Scale lin @20mA
Press EXIT to return to main menu.
Scale lin @4mA is modified in the same way.
Sidebar:
There’s a lot of flexibility in the 4-20 mA input scaling & the corresponding pump speed but
most users will leave 4mA=0% and adjust the mA @ 100% to allow 0-100% pump operation
over a narrower range of 4-20 mA input.
For example, if you wish 0-15% of the 4-20 mA input to control the pump from 0-100%
Edit
Scale lin @20mA for 6.4mA = 100%
& leave Scale lin @ 4 mA unchanged at 4.0mA = 0%
Setting the mA level below 4.0mA will set the mA level to 4.0mA
Setting the mA level above 21.0mA will set the mA level to 21mA
Setting the % above 100% will set the % to 100%. The % level cannot be set below 0%.
Refer to Appendix B for notes on 4-20mA Input scaling.
If you set % span to zero in error, the pump will turn OFF.
Note that you could make the current loop response reverse acting so that an increasing loop
current will cause a decreasing pump %.