background image

02-00002-01-en, July 2007

1(4)

TAC Xenta

®

 421A/422A

Universal Input and
Digital Output Module

Configuration Instruction

02-00002-01-en

Physical Inputs and Outputs

TAC Xenta 421A/422A can be used as a normal Xenta I/O
module or as a certified L

ON

M

ARK

® device. It has

4 Universal Inputs (UI)

5 Digital Outputs (DO)

In addition, TAC Xenta 422A has five manual switches, one
for each DO that can be set

manual Off

manual On

Auto

To configure the inputs and outputs, and to specify the
transmission of values, either ordinary TAC Menta®/Xenta
configuration or 

nci SNVTs are used. The usage is explained

overleaf ("SNVT vs TAC Xenta I/O module Communication".)

The use of SNVTs requires explicit information listed below.

UI Configuration

Each of the four UI:s (1-4) is configured with

nciInput1-4

0 = not connected (default value)
1 = 1.8 kohm thermistor
2 = DI, green indication
3 = 0-10 V
4 = 0-20 mA
5 = 10 kohm thermistor
6 = DI, red indication
7 = DI, green inverted indication
8 = DI, red inverted indication

If configured to be a digital input (DI, any type), its function is
further determined by the corresponding bit in

nciDigInNONC:

DI 1

DI 2

DI 3

DI 4

If bit=0: NO, normally open (default value)

If bit=1: NC, normally closed

Pulse counting is not available for SNVT communication.

UI Values

Depending on the UI configuration, each UI n=1-4 generates
a valid value in one of these (the other two are set invalid):

nvoAnalog1-4 (0-10 V or 0-20 mA, converted to 0-100%;

invalid=163.835)

nvoDigital1-4 (DI, any type)

Off: state=0, value=0
On: state=1, value=100
Invalid: state=255

nvoTemp1-4 (thermistor, any type; invalid=327.67)

UI Value Transmission

The UI value will be transmitted

a) when the change in value is large enough (set individually

per UI)

b) at a specified time interval (common for all UIs)

a) is determined by

nciSndDelta1-4 (dimensionless; default value=2)

Size of change to cause transmission
Ex.: 1 means
- if configured as analog input: 1%
- if configured as temperature input: 1 °

If the UI is configured as a digital input, a status change will
always be transmitted.

b) is determined by

nciSndHrtBt

"Heartbeat" interval in seconds  (default=60)

A valid and configured UI value will be sent at least once
during each interval regardless of change.

The transmissions will be distributed over time to avoid
momentary communication overload.

DO Values

The digital output values to the output (DO, n=1-5) are
received as:

nviDO1-5

switch:state
state=0 or >1: Off
state=1: On

For the TAC Xenta 422A, the DO values may be overridden
by manual switches. Their status is indicated in

nvoHandBoard1-5 switch:state.

state=0: manual Off
state=1: manual On
state=255 ('invalid'): Auto

Any DO status change will immediately be transmitted.

DO Values in the Off-line Condition

The DO values are expected to be updated regularly.
However, this may be prevented by communication failure or,
temporarily, after power-up.

    LONMARK CONFIGURATION AND VARIABLES

(continued ...)

Bit 0

Bit 15

Reviews: