FC 104 - Pulse Input / Totalization

The pulse input/totalization function code interfaces a controller to a selected channel of an IMDSM04 pulse input slave module. The IMDSM04 module conditions, converts and processes pulse inputs into analog signals. It has eight inputs that can be processed in three modes: period, frequency and totalization. Function code 104 configures a signal to output a totalized value. Function codes 102 and 103 process signals in the period and frequency modes, respectively. Function code 109 processes the duration of the input pulses. Each input channel must have only one pulse input block configured.

 

Outputs:

Blk

Type

Description

N

R

Current totalized value X gain

N+1

B

Totalized value alarm:

0 = no alarm

1 = alarm

N+2

B

I/O module communication status:

0 = good

1 = bad

 

 

 

Specifications:

Spec

Tune

Default

Type

Range

Description

S1

N

0

I

0 - 63

Expander bus I/O module address of IMDSM04 module

S2

N

1

I

1 - 8

Selected channel

S3

N

0

B

0 or 1

Pulse trigger level:

0 = low to high transitions

1 = high to low transitions

S4

Y

0.000

R

Full

Starting value

S5

N

0

I

0 or 1

Totalization direction:

0 = positive

1 = negative

S6

N

0

I

Note 1

Block address of reset flag:

0 = continue totalization

1 = reset totalization

S7

N

0

I

Note 1

Block address of hold flag:

0 = continue totalization

1 = hold accumulated total

S8

Y

0

B

Full

Automatic reset on alarm limit flag:

0 = off

1 = when alarm, reset to S4 + alarm overrun

S9

Y

1.000

R

0 - 9.2E18

Gain

S10

Y

9.2E18

R

Full

Alarm Limit

 

NOTES:

1. Maximum values are: 9,998 for the BRC-100, IMMFP11/12 and 31,998 for the HAC

 

 

104.1Explanation

 

In the totalization mode, an internal counter records the number of input pulses up to 1.9 x 1019 or until the counter resets.  The trigger transition level, totalization direction, and starting value are configurable. The reset input sets the totalizer to the starting value. This is useful for reset events based on time. An automatic reset on alarm can be specified. This allows for the totalizer to be set to the starting value plus the alarm overrun when an alarm condition occurs. This can be used for reset events based on accumulated totals since the count is not lost. A configurable alarm limit determines alarm conditions. A hold input provides temporary stop totalization, and a gain parameter provides a scaled output.

 

 

104.1.1Specifications

 

S1 - SLVADR

I/O module expander bus address of the IMDSM04 module. Valid addresses are zero through 63.

 

S2 - CHNL

Identifies the input channel being monitored. IMDSM04 modules have eight input channels. Refer to the IMDSM04 Pulse Input Module product instruction to identify the channel associated with each input.

 

S3 - PTRIG

Defines the type of signal transition that triggers the counter response.

0 = response on low to high transitions

1 = response on high to low transitions

 

S4 – STRT

Initial value of the count on startup and function code reset. Specification S4 plus the alarm overrun is the value of the count after an alarm if the alarm limit flag is set to automatic reset.

 

S5 - DIR

Direction of the count.

0 = positive

1 = negative

 

S6 - RST

Block address of the reset flag.

0 = continue totalization

1 = reset count to starting value (S4)

 

S7 - HOLD

Block address of the accumulated total hold flag. When a hold flag (logic 1) releases (logic 0), the counter resumes counting without resetting.

0 = continue totalization (normal)

1 = hold accumulated total

 

S8 - AUTO

Automatic reset on alarm flag. This value determines the counter action when the alarm limit is reached. The counter can either continue counting beyond the alarm limit, or reset the counter to S4 plus alarm overrun.

0 = off

1 = reset to S4 plus alarm overrun when alarm limit is exceeded

 

NOTE: Alarm overrun is the current count reset to the difference between the counter and the alarm limit. This allows the block to correctly detect the next alarm without losing track of the true counts.

 

S9 - K

Defines the gain multiplier. Gain scales the output to a useful value. A negative gain does not affect the output.

 

S10 - ALRM

Alarm limit. When the alarm limit is reached, the N+1 output becomes a logic 1, signaling the system that the totalized value is in alarm.

 

 

 

104.1.2   Outputs

 

N

Current totalized value times gain.

 

N+1

Total value alarm indicator.

0 = no alarm

1 = alarm

 

N+2

I/O module communication status.

0 = good

1 = bad

I/O modules are bad if:

• There is an illegal I/O module response.

• There is no I/O module response.

• There is an IMDSM04 counter overflow (count > 1.9 x 1019).

or

• There is a counter overflow.

 

NOTE: A counter overflow indicates the counter input is transitioning too fast for the configured scan rate of the segment running the function code. This is a false indication of a bad I/O module and this indication should be considered when configuring this block.