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6 special i/o functions, 3 clearing the analog input configuration, 1 on/off and pid control – Infinite Peripherals SCOM-100 User Manual

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SCOM-100, User guide

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4.5.3 Clearing the analog input configuration

Any analog input configuration settings such as alarm, naming, messaging and scaling can be cleared
using the command:

1210,m,n

1210: Command

ID

m:

Module number (0 for SCOM-100 main unit, 1-4 for AI-4 expansion
units)

n:

Input number (1-2 for SCOM-100 main unit, 1-4 for AI-4 expansion units)

4.5.4 Setting the analog inputs alarm deadband

A special command is available to configure alarm deadband (hysteresis) for all
analog inputs. Alarm deadband is a small range in the total scale of the input signal
where alarm states remain indifferent, holding on their last value - in order to avoid
frequent SMS transmissions.
The Alarm deadband is given as a percent of the total scale.

1290,d

1290: Command

ID

d:

Alarm deadband value in % up to 5% of the total scale (0-5% in 0.1
steps). Example: d =2.3%

4.6 Special I/O Functions

4.6.1 ON/OFF and PID control

Up to four ON/OFF or PID control function blocks are available. Each block uses an analog input
for measuring the process value and a digital output for control.

Function block configuration

1250,id,m,n,m1,n1,sp,g,it,dt,ct,h

1250: Command

ID.

id:

Function block ID (1-4).

m:

Module number (0 for SCOM-100 main unit, 1-4 for AI-4 expansion
units).

n:

Input number (1-2 for SCOM-100 main unit, 1-4 for AI-4 expansion
units).

m1:

Module number (0 for SCOM-100 main unit, 1-8 for DI-42 I/O expansion
units).

n1:

Output number (1-4 for SCOM-100 main unit, 1-2 for DI-42 I/O
expansion units).

sp:

Set point value in the range of the analog input scale.

g:

‘Gain’ value (P) between 1 and 100%. The block function depends on
the ‘Gain’ value: A zero value selects the ON/OFF control function. A
non zero value selects the PID function.

it:

‘Integral time’ (I) value between 1-1000 sec. A zero value disables the
integral part (not relevant for ON/OFF control).

dt:

‘Derivative time’ (D) value between 1-200 sec. A zero value disables the
drivative part (not relevant for ON/OFF control)..

ct:

‘Cycle time’ value between 1 and 15 minutes, representing the pulse
width modulation period of the digital output (not relevant for ON/OFF
control).