There is a 4 to 20 mAdc signal that must be limited to 7 mA
regardless of how low the signal drops, in order to keep a valve partially
open even when the control signal may try to close it. Also the low limit
needs to have adjustability independent of the high limit, in case conditions
change.
For preventing the signal dropping below 7 mA, you can use a Limiter model
M2LMS. Adjust the low limit to 7 mA - 25% of full-scale. The M2LMS output
tracks the input signal above 7 mA, however it holds 7 mA once the input
goes below it.
Controls for setting the high and low limits are fully independent. Both
limits are continuously adjustable within the range from 0 to 100% of full-scale
with front -accessed multi-turn screwdriver adjustments, and monitor ports
are also accessed on front for easy adjustments monitoring 0 to 10 Vdc on
a voltmeter proportionally to the 0 to 100% setpoint. |
