Thermo Ramsey - Hoferick Engineering GmbH

Thermo Fisher Scientific Installation
REC 4175 Rev B
Installation
1.6.3 Print Functions
Periodical and command prints can be obtained by connecting a serial printer to
the Comm output on the motherboard or an optional communication board.
Time and date are permanently stored in the battery-backed memory. The entire
set up of the instrument can also be printed out.
1.6.4 Communication Functions
There are two types of standard communication functions. Each is discussed
below:
• Serial Communications – The communication protocol allows a remote
intelligent device to read the contents of the registers and write to some
registers.
During the communication activity, the Micro-Tech 3101 always acts as a
Slave, meaning it responds to a request from a Master device on the line, but
never attempts to send messages out.
One electrical interface may be selected and accessed through one
communication port. Up to three communicaiotn boards may be installed.
• Field Bus I/O – Allen-Bradley RIO or Profibus-DP I/O, or DeviceNet
communication protocol board is typically used to transfer I/O images
between a main PLC and the remote devices (normally remote I/O racks –
rack adapters) or to transfer (read and write blocks of data with intelligent
remote devices (node adapters), the Micro-Tech 3101 in this case.
The Remote I/O is a typical master/slave communication where the main
PLC is the master or scanner and the remote devices are slaves or adapters.
1.7 Functional Description
This section describes technically, how the Micro-Tech 3101 performs each
particular duty.
1.7.1 Measuring Functions
1.7.1.1 Instantaneous Flow Rate Calculation
The signal measured by the load cell(s), which represents the weight per unit
length of the belt (lbs/ft), is multiplied by the signal measured by the speed
transmitter, which represents the belt speed (ft/mn). The result of this operation
is the instantaneous flow rate (lbs/ft x ft/mn = lbs/mn) that is then multiplied by
suitable constant to obtain the value in the required engineering units (kg/h,
ton/h, etc.). An adjustable damping filter is provided separately for displayed
rate and current outputs.
1.7.1.2 Flow Totalization
The total is accumulated by multiplying weight per unit length times the
incremental length and totalizing the result in engineering units.
Three totalizing memories are provided:
• The first memory (Master Total) is not re-settable to guarantee the data is
not lost because of unwanted reset.
• The second and third memories (Reset and Operator Total) are re-settable
by the operator and normally used for shift or daily Totalization.
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