
Physical Output
Description
Communications. This is useful when you want bits in
a PLC to reflect logical outputs in your batch
controller.
Acc Switch 1
through 4
Not used in this application
EMT Settings
EMT stands for External Mechanical Totalizer. You can connect almost any pulse
counter to the EMT outputs of the controller, and have it advance in parallel with the Total
parameter in the MC³. For details on how to connect a counter, see the MC³ hardware
manual at
.
Divisor
This is the value used to scale the output. If it is set to 1 then there is one pulse for every
pound or kilogram that is totalized. If set to 100, there must be 100 pounds or kilograms
totalized before a pulse is sent to the external totalizer. Limits are minimum 1 and a
maximum of 100,000.
Pulse Width
This value is the length (on-time) in seconds for the outgoing pulse. A mechanical
counter will require a longer pulse than an electronic. The pulse output from the controller
is buffered, in order to allow slow counters to “catch up”. The recommended value for a
mechanical totalizer is 0.10, and 0.01 for an electronic totalizer. Limits are 0.01 to 5.0.
The duty cycle is 50% at full pulse rate.
Comm Settings
Serial Communications provides the means to exchange information between the MC³
Controller and other devices. There are two serial ports, Comm 1 and Comm 2.
On Comm 1, you can run a Merrick proprietary protocol, called Scalenet, or a subset of
Modbus ASCII or RTU, which is a Modicon protocol in the public domain.
On Comm 2, you can connect a printer with a serial interface, or you can run a subset of
DF-1, which is an Allen-Bradley protocol in the public domain.
Through interfaces, it is possible to connect to many Industrial Networks, such as
ProfiBus, DeviceNet, ControlNet or EtherNet/IP. More information on network
connections and available Merrick communications solutions can be found at
.
There are PC based software products available from Merrick that utilizes ScaleNet.
WinMerik allows you to
•
Upload and download all MC³ parameters to and from PC files.
•
Monitor, in real time, up to 10 MC³ registers, and log them to a CSV file periodically.
•
Access, in real time, up to 10 MC³ registers using Dynamic Data Exchange (DDE).
For more information, refer to
WARNING:
Failure to program communications correctly can result in the operational failure of the
controller. It is possible, for example, to write a non-valid floating point number to a
controller parameter. This will cause a controller fatal exception. You will have to reset all
parameter to their default values, and then enter all of them.
35.00.EX O&M Manual
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Содержание MC3 35.00.EX
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