The gain press sen and offset press sen fields can scale an optional external
pressure sensor, so the sensors output voltage range converts to the appropriate
pressure range on the UVM. The use of a pressure sensor as a DP monitor is active only
when the use press sens as DP selection is active. The pressure sensor can be used to
monitor the DP pressure across the valve and give a 0 CFM output voltage if the pressure
falls below the value set in the no flow press field, typically 0.6 in. W.C. See Table 4 for more information on
scaling details.
Note: When an analog pressure
sensor is used with a voltage output connected to the sens_In pin, use the following
scaling. The scaling is derived from : 0 V = 0 counts, 5 V = 4095 counts = x Press =
(x – Offset) * Gain
-
Gain = ( ( Ph – Pl ) / ( Vh – Vl ) ) * ( 5 / 4095 )
-
Offset = ( 4095 / 5 ) * ( Vh – ( Ph * ( ( Vh – Vl ) / ( Ph – Pl ) ) )
-
Where Vh is the sensor voltage at the high-pressure Ph, and Vl is the low voltage at the low-pressure Pl.