Endress+Hauser Liquiline System CA80TN, Operating Instructions Manual

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Liquiline System CA80TN Operation
Hauser 91
• Start date = 01.01.2020
• Start time = 12:00:00
• Signal duration = 05:00:00
• Period = 24:00:00
3. Create Formula mathematical function.
Menu / Setup / Additional functions / Mathematical functions
• MF1: Formula
• Tracking = On
• Source A = Time switch 1
• Source B = Time switch 2
• Formula = 18.0 + 3*NUM(A) + 2*NUM(B)
Explanation: NUM converts the logical value to a numerical value and thus enables
multiplication.
• 3*NUM(A) results in the value 3.0 from 08:00 to 17:00 and 0.0 outside of this time
period.
• 2*NUM(B) results in the value 2.0 from 12:00 to 17:00 and 0.0 outside of this time
period.
The formula thus yields one of these analog values depending on the time: 18.0, 21.0 or
23.0. This analog value can be used as a set point for a temperature controller.
Example 2: Time-based condition
A pump should switch on (via a relay) for 10 minutes every 2 hours. This only applies if
the pH value is lower than 4.0.
1. Program Time switch 1 :
• Start date = 01.01.2020
• Start time = 00:00:00
• Signal duration = 00:10:00
• Period = 02:00:00
2. Create Formula mathematical function.
Menu / Setup / Additional functions / Mathematical functions
• MF1: Formula
• Tracking = On
• Source A = Time switch 1
• Source B = pH value of a Memosens pH input
• Formula = A AND(B<4.0)
3. Use the formula as the data source of a relay.
Menu / Setup / Outputs / Relay [x:y]
• Function = Formula
• Operating mode = Static signal
• Source of data = MF1: Formula
The formula yields a logical value (TRUE or FALSE) and is thus suitable to trigger a relay
directly in the static operating mode. Time switch 1 provides a TRUE value for 10 minutes
every 2 hours but only if the pH value has dropped to below 4 at the same time.