Monitoring and Operating the Controller
216 UDC3500 Universal Digital Controller Product Manual 3/07
4.13 Input Math Algorithms
Introduction
This controller has two input algorithms available, some that are standard on any
instrument with two or more analog inputs and some that are available as part of the
Math option. Each algorithm can be configured to provide a derived (calculated) PV or a
derived Remote Setpoint. Up to three inputs may be applied to the calculation. In
addition, the two algorithms may be “linked” to combine two calculations by configuring
one algorithm to be an input to the other algorithm.
Standard functionality
The following algorithms are provided as standard on all instruments with two or more
analog inputs: Weighted Average, Feedforward Summer, Feedforward Multiplier, or
Relative Humidity.
Math Options
The Math option provides additional algorithms plus two Characterizers, Totalizer, and
Polynomial functions.
Input algorithm selections
Algorithm selections are made in Section 3 – Configuration. The following function
prompts can be found in the Algorithm Set Up group:
IN ALG1
IN ALG2
These selections include the following algorithms:
Weighted Average
Feedforward Summer
Relative Humidity
Summer
Hi Select
Lo Select
√ Multiply Divide
√ Multiply
Multiply Divide
Multiply
Feedforward Multiplier
Carbon Potential (several types)
Oxygen
Dewpoint
The formulas for these selections are given in Section 3.11.