KRAL BEM 500 - Page 47

16 Appendix
16.1 Glossary
Designation Meaning
Pulse (signal)
o A rising edge is followed after a certain period by a falling edge
o Corresponds to the square wave signal
Pulse output
o Generates pulses with 24V signal level conforming to the scale of an input variable
Pulse input
o Processes pulse signals
Pick up (A/B)1
o Sensor that generates one pulse per defined flow rate
Pick up (A/B)2
o Sensor that generates one pulse with +90° phase shift per defined flow rate
o Allows a flow direction recognition in combination with Pick up1
Incremental encoding in-
put
o Processes two square wave signals out of phase by 90°
o Provides a counting function under consideration of the flow direction and a frequency measuring
function
K-factor
o Number of pulses per flow volume unit
o Characteristic of a flowmeter
Linearization
o Maps the dependence of the K-factor of a flowmeter across the flow range in an electronic unit
Linearity
o Dependence of the K-factor across the flow range
Mass calculation
o Volumetric values are converted into mass values under consideration of the temperature via the
density table
Modbus connection
o Digital communication with connected users
Modbus interface
o Makes available the hardware (e.g. RS232) and software (e.g. Modbus RTU protocol) required for
digital communication
Rate
o Volume per time unit
Reaction time
o Time for a change of 99.9% of the actual jump
Square wave signal
o Pulse signal with square wave form
Relay output
o Potential-free change-over contact
Return line
o Line from the consumer back to the reservoir
Group error message
o Message that indicates the occurrence of at least one error
Threshold value
o Value at which an action is triggered when it is overpassed or underpassed
Serial interface
o Sends or receives data in chronological sequence
Scale
o Assigning of a maximum input value to a maximum output value
Temperature input
o Processes signals of a temperature sensor
Temperature sensor
o Converts the physical value temperature into an electrical value (e.g. resistance)
Temperature compensa-
tion
o Consideration of the current temperature at the volume calculation and mass calculation in order to
compensate density changes
Total
o Volume values that have been measured since the last reset
Total flow
o Quantity that has passed the flowmeter since the last reset
Total consumption
o Quantity that has been consumed since the last reset
Consumption
o Consumption Q=QA-QB
Link channel AB
o Q=QA-QB or Q=QA+QB
Volume calculation
o The volume is converted to a standard temperature by means of the density table and the
temperature
Volume measurement
o The volume that passes the flowmeter is calculated from the K-factor [P/l] and the pulses of the
flowmeter
Volumeter
o Flowmeter
Supply line
o Line from the reservoir to the consumer
Circulation ratio
o Ratio of supply rate/consumption (A/(A-B))
Reset
o Setting the variable to the value 0
Cycle time
o Time section in which all the calculations are carried out, inputs processed and outputs operated
Operating instructions
OIE 12en-GB Edition 2020-03
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