Bronkhorst®
Instruction Manual EL-FLOW® Prestige
9.17.084N
33
Access
R
Parameter value can be read
W
Parameter value can be written
Parameter is secured and only accepts values if parameter
Init Reset
is set to 'unlocked' first
Range
Some parameters only accept values within a certain range:
[x]
Minimum value of the range
[y]
Maximum value of the range
FlowDDE
Parameter number within FlowDDE
FLOW-BUS
Within the FLOW-BUS protocol (ProPar when using RS-232 communication), parameters are identified by a unique
combination of a process number and a parameter number:
[Pro]
Process number
[Par]
Parameter number
Consult the
RS-232 manual
(document no. 9.17.027) for detailed information.
Modbus
In the Modbus protocol, parameters are accessed by specifying their unique decimal register number or corresponding PDU
address (Protocol Data Unit). The PDU address is the hexadecimal translation of the register number minus 1, e.g. register
number 1 corresponds to PDU address 0x0000, register number 11 corresponds to PDU address 0x000A:
[address]
Hexadecimal PDU address
[register]
Decimal register number
Modbus address blocks are two bytes big. Larger data types use up to 8 subsequent address blocks, resulting in a
maximum variable length of 16 bytes. Values longer than the maximum length are truncated.
Other interface protocols
Consult the specific fieldbus manual for accessing parameters using fieldbus communication (see
).
3.9.2
Measurement and control (basic)
Measure
Type
Access
Range
FlowDDE
FLOW-BUS
Modbus
Unsigned int
R
0…41942
(65535*)
8
1/0
0x0020/33
This parameter indicates the flow metered by the instrument. The signal of 0…100% is presented in a range of 0…32000.
The maximum measured value output is 131.07%, which translates to 41942.
A floating point pendant of the measured value is also available in the capacity unit for which the instrument was set; see
section
Measurement and control (advanced)
*In case the instrument is prepared for bi-directional measurement, the negative signals with an output range of -
73.73…-0.003% are represented by the range of 41943…65535, whereas the positive signals 0…131.07% are still
represented by the range of 0…41942. (FlowDDE converts the numbers to negative values automatically).
Setpoint
Type
Access
Range
FlowDDE
FLOW-BUS
Modbus
Unsigned int
RW
0…32000
9
1/1
0x0021/34
This parameter is used to set the required flow rate for the controller. The signals have the same range as
Measure
, but the
setpoint is limited between 0 and 100% (0…32000).
A floating point pendant of the setpoint is also available in the capacity unit for which the instrument was set; see section
Measurement and control (advanced)
To convert
Measure
and
Setpoint
to actual volume flows, use parameters
Capacity
and
Capacity Unit
