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6 changing default control mode – Bronkhorst EL-FLOW Base 2014 User Manual

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BRONKHORST HIGH-TECH

Kopen (RespOpen0)

Type

Access

Range

FlowDDE

FlowBus

ModBus PDU

Unsigned char

RW 

0…255

165

114/18

0x0E52/3667

Controller response when starting-up from 0% (when valve opens).

Value 128 is default and means: no correction.

Otherwise controller speed will be adjusted as follows:

(128-RespOpen0)

New response = old response * 1.05

Knormal (ContrResp)

Type

Access

Range

FlowDDE

FlowBus

ModBus PDU

Unsigned char

RW 

0…255

72

114/5

0x0E45/3654

Controller response during normal control (at setpoint step)

Value 128 is default and means: no correction.

Otherwise controller speed will be adjusted as follows:

05

.

1

)

128

(

_

_

contresp

old

response

new

response

=

Kstable (RespStable)

Type

Access

Range

FlowDDE

FlowBus

ModBus PDU

Unsigned char

RW 

0…255

141

114/17

0x0E51/3666

Controller response when controller is stable (within band of 2% of setpoint)

Value 128 is default and means: no correction.

Otherwise controller speed will be adjusted as follows:

05

.

1

)

128

(

_

_

respstable

old

response

new

response

=

4.1.6 Changing Default Control Mode

Instruments are delivered with either analog or digital signal as default setpoint, depending on

customer’s requirement.

After every (power on) reset the instrument will return to its default control mode.

The default control mode can be changed with the following parameter:

IOStatus

Type

Access

Range

FlowDDE

FlowBus

ModBus PDU

Unsigned char

RW 

0…255

86

114/11

0xF258/62041

Bit 6 [7..0] represents the former analog jumper.

1 = default control mode is analog

0 = default control mode is digital

Procedure for changing default digital operation to default analog operation:

• Read IOStatus
• Add 64 to the read value

])

40

0

[

(

x

OR

• Write IOstatus

Procedure for changing default analog operation to default digital operation:

• Read IOStatus

Page 28

EL-FLOW Base Series Mass Flow Controllers

9.17.061