12
2.7
Communication channels
• The ref. 422684 422684 has an integrated RS-485 communication port named COM1.
• The communication settings menu has three parameter sections (n=1 ... 3) for setting the communication ports.
2.8
Inputs, outputs, internal variables, counters, analog inputs
• The inputs and outputs are identified by a code and a seuential number. For example, the digital inputs are named INPx,
where x is the input number. Similarly, the digital outputs are named OUTx.
• The input/output numbering is based simply on the assembly position of the expansion modules with a seuential num-
bering from the top down.
• Up to 6 analog inputs (AINx) can be managed coming for external sensors (temperature measurements, consumption,
pressure, flow rate etc.). The value read by the analog inputs may be converted into any engineering unit shown on
the display and made available on the communication bus. The uantities read by the analog inputs are shown on the
specific page. Limit thresholds (LIMx) may be applied to each one, which in turn can be connected to an inner or outer
outputs, or inserted in a PLC logical function.
• The expansion I/O numbering starts from the last I/O fitted on the base unit. For example, for digital inputs, INP1…INP12
on the basic unit and thus the first digital input on the expansion modules will be named INP13. The I/O numbering is
shown in the following table:
CODE
DESCRIPTION
BASIC
EXP
INPx
Digital inputs
1…12
13…20
OUTx
Digital outputs
1…11
12…20
COMx
Communication ports
1
2...3
AINx
Analog inputs
-
1…6
AOUx
Analog outputs
-
1…6
RALx
Remote relays for alarms/states
-
1…24
• Like the inputs/outputs, there are internal variables (bit) which may be associated to the outputs or combined. For
example, limit thresholds can be applied to the measurements performed by the system (voltage, current etc.). In this
case, the internal variable, named LIMx, will be activated when the measurement is beyond the limits defined by the
user by means of the respective setting menu.
• Furthermore, up to 8 counters (CNT1…CNT8) which can count pulses come from the outside (thus from INPx inputs) or
the number of times for which a given condition occurred. For example, by defining a LIMx threshold as counting source
it will be possible to count how many times a measurement exceeds a given value.
• The following table shows all the internal variables managed by the ref. 422684 with their range (number of variables
per type).
CODE
DESCRIPTION
RANGE
LIMx
Limit thresholds on measurements
1…16
REMx
Variables controlled remotely
1…16
UAx
User alarms
1…8
CNTx
Programmable counters
1…8
PLCx
PLC logic variables
1…32
TIMx
Timer
1…8
Limit thresholds (LIMx)
• The LIMn limit thresholds are internal variables the state of which depends on a measurement of those performed by
the system going beyond the limits defined by the user, e.g. total active power higher than 25kW).
• To speed up setting considering that each threshold can span across an extremely wide range, each threshold can be
set to a base value + a multiplying coefficient
(e.g.: 25 x 1k = 25000).
• Two thresholds are available for each LIM (upper than lower). The upper threshold must always be set to a value higher
than the lower value.
• The meaning of the thresholds depends on the following functions:
2. Operating modes