7 md transducer block – Flowserve 400MD Logix User Manual

Page 42

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Calibration Auto: allows the user to specify the auto calibration (default) or to enter into a job calibration mode.

LX_SPI_STATUS_FLAGS Should a loss of communications occur between the fieldbus card and positioner card this parameter sets the fail mode
of the valve. Nothing selected will cause the positioner to hold the last known command should a loss of communications occurs.

STROKE_TIME_UP: Allows the user to limit the stroking speed of the positioner. Input the number of seconds for the desired opening stroke
speed. Disable this feature by writing 0 to the variable.

STROKE_TIME_DN: Allows the user to limit the stroking speed of the positioner. Input the number of seconds for the desired closing stroke
speed. Disable this feature by writing 0 to the variable.

CURVE_SELECT: This parameter allows the user to select what type of characterization curves the positioner will use. The selections are Equal
Percent, Quick Open, or Custom. If Custom is selected, the parameters CURVEX and CURVEY must be initialized.

NVRAM_WRITE_CYCLES: This is a diagnostic parameter that allows the user to monitor the number of times the NVRAM is written to. This
can be a useful diagnostic tool for checking if the host system is writing to the Fieldbus board memory too often. This is often a configura-
tion error in the host system setup. Excessive write cycles can cause configuration upsets and possible communications slowdowns and
errors. It also will shorten the operational life of a Fieldbus device by exceeding the finite number of write cycles NVRAM chips can be used
reliably to. These devices typically have a minimum 10,000,000 write cycle endurance. Even though this is a very high number that would typically
never be reached during the operational life of the device, a misbehaving host configura tion routing could drive up the number of write cycles very quickly,
and should be corrected as all devices in the configuration will be adversely affected by this continuous download.

8.7 MD Transducer Block

The MD Transducer block contains the parameters used by the advanced and pro model of the Logix 3400MD. These parameters are used for
diagnostics and error detection of the system.

Table 8.8 Transducer Block Parameters

Index

Origin Name

Store Date Type

Default Value

0

STND XDTB_MD

SRW

Record

BLOCK

0

1

STND ST_REV

SR

Simple

UNSIGNED16

1

2

STND TAG_DESC

SRW

Simple

OCTET_STRING

“7 “

3

STND STRATEGY

SRW

Simple

UNSIGNED16

2

4

STND ALERT_KEY

SRW

Simple

UNSIGNED8

4

5

STND MODE_BLK

SRW

Record

MODE

0x01;0x01;0x11;0x10

6

STND BLOCK_ERR

R

Simple

BIT_STRING

0

7

STND UPDATE_EVT

RW

Record

ALARM_EVENT

0;0;0,0;0;0;0;0

8

STND BLOCK_ALM

RW

Record

ALARM_DISC

0;0;0,0;0;0;0;0;0;0

9

STND TRANSDUCER_DIRECTORY

NR

Array

UNSIGNED16

0

10

STND TRANSDUCER_TYPE

NR

Simple

UNSIGNED16

106

11

STND XD_ERROR

R

Simple

UNSIGNED8

0

12

STND COLLECTION_DIRECTORY

NR

Array

UNSIGNED32

0

13

MFG

LD_MD_MODE

R

Simple

UNSIGNED8

0

14

MFG

MECHANICAL_STATUS

R

Simple

BIT_STRING

0

15

MFG

MECHANICAL_MASKING

NRW

Simple

BIT_STRING

0

16

MFG

VALVE_TRAVEL_DISTANCE

R

Simple

FLOATING_POINT

0

17

MFG

VALVE_TRAVEL_HIGH_START

RW

Simple

FLOATING_POINT

0

18

MFG

VALVE_TRAVEL_HIGH_END

RW

Simple

FLOATING_POINT

0

19

MFG

VALVE_TRAVEL_PERCENT_YELLOW

NR

Simple

FLOATING_POINT

0

20

MFG

VALVE_CYCLE_COUNT

R

Simple

UNSIGNED32

0

21

MFG

VALVE_CYCLE_HIGH_START

RW

Simple

UNSIGNED32

0

22

MFG

VALVE_CYCLE_HIGH_END

RW

Simple

UNSIGNED32

0

23

MFG

VALVE_CYCLE_PERCENT_YELLOW

NR

Simple

FLOATING_POINT

0

24

MFG

PST_TIME_BREAKAWAY

NR

Simple

FLOATING_POINT

0

25

MFG

PST_PRESSURE_DIFF

R

Simple

FLOATING_POINT

0

Logix 3400MD Digital Positioner LGENIM3405-02 11/13

42

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