CIRCUTOR MDC-20 - Manual (Page 10)

MDC-20
Page 10 of 58 User Manual
2.1 Internal WEB SERVER
The MDC-20 has an internal WEB server that allows you to connect to an Ethernet network.
This allows the user to read internal variables in real time or obtain historic logs as graphics or
tables.
To connect to the Ethernet network, the MDC-20 must be correctly configured. Once configured
and integrated in the Ethernet network, the unit variables are visible to the user via a
conventional Internet browser, provided the appropriate Java virtual machine is available and
installed on the computer. The machine is available at the following address:
http://www.java.com/es/download. Another way of viewing the variables on the unit is through
the PowerStudio® Scada Client which must be installed on the computer.
To communicate with the unit via the web and view the variables on the browser, the user must
access an IP address or an alias in DHCP (Dynamic Host Configuration Protocol) page name
format:
http://xxx.xxx.xxx.xxx ,
or the DHCP name, http://name_dhcp ; where:
xxx.xxx.xxx.xxx is the IP address assigned by the user and
name_dhcp is the name assigned and authenticated by the local area network (LAN) name
server.
2.2 XML server
XML, which stands for eXtensible Markup Language, is a mark-up language developed by the
World Wide Web Consortium (W3C) used to store machine-readable data.
XML is a standard for exchanging structured information between different platforms
(databases, tables of variables, text editors, spreadsheets, etc.)
The XML server is an excellent tool for integrating MDC-20 with external applications.
2.3 Digital inputs
The MDC-20 has 8 digital inputs, whose function is to count impulses from external analyzers or
to detect the logic state of external sensors (voltage free contacts). The contacts for activating
the unit's digital inputs must be voltage-free contacts (the device provides an internal power
supply). The unit detects an open or closed contact between a common terminal and the
corresponding input terminal.
2.3.1 Impulse counter function
It is normal for fluid or energy meters to be equipped with an impulse output with a frequency
proportional to the measured energy or flow. The MDC-20 can be used as a centralising
metering unit, using its 8 digital inputs for reading as many meters as available inputs. Note that
this enables centralising electrical energy metering, as well as water, gas, hot water meters, etc.
which have a pulse output channel.
The unit is equipped with 8 non-volatile memory logs that add together the logs of the above-
mentioned energy meters. Each log is 32 bits (4 bytes), so it counts a maximum of up to
4,294,967,295 impulses. When a log reaches said maximum value, the next impulse resets the
energy meter to zero.