Thermo Scientific APEX 100, User Manual, Page: 322 / 442

Page 322
Thermo Scientific APEX User’s Guide
Get Remote Access to APEX Parameters
One of the main advantages of the Modbus Communications Card is that it allows you to
set up many APEX parameters remotely using Modbus protocols. To do this, you will
need a desk-top computer (linked via your network to the Modbus card) running an
application such as Modscan, PC Master, or other similar program. Please note the
following minor limitations.
• You cannot access the communications menu remotely. All communication
parameters (such as IP address, baud rate, and so forth) must be changed using
the APEX display panel.
• Some parameters cannot be set remotely for safety or other reasons, because a
person must be present—for example, to pass a test package through the APEX.
Change Products Remotely
The Modbus Communications Card allows you to change products remotely. By changing
a single Modbus register (number 41045) and the parameter-change-notification coil
(register 16385) to one (1), all APEX settings for the designated product are
immediately updated.
Get Real-Time Statistics from the APEX
The Modbus Communications Card also allows you to get real-time operating and other
statistics from the APEX. In other words, you can monitor the detector’s performance
remotely, without going down on to the factory floor, allowing you to monitor current
reject totals, detect level, and so on.
Back Up Critical APEX Settings
And finally, the Modbus Communications Card allows you to back-up (externally, using
your pre-existing database software) all of the detector’s critical settings—including
performance statistics, specific product settings, detect levels, reject counts, and so on.
Thus, in the event of a catastrophic failure, you can quickly and easily restore all the
APEX settings—the ones you have spent so much time, money, and effort perfecting.
Regular back-ups are also useful for checking that all APEX parameters are set correctly,
and are very helpful, should you ever need to contact Thermo Fisher Scientific’s
technical-support personnel—as described in the “Contacting Thermo Fisher Scientific”
section at the end of the manual—for troubleshooting assistance.
Engineering Details
The Modbus Communications Card is a microprocessor card that handles all field-bus
communications. All data read and written from the field bus is held internally in the
card’s dual-port random-access memory (RAM). Various registers are defined, and these
map data held in the APEX onto the Modbus’ RAM. Because the Modbus Communications
Card does not support fully bi-directional data transfer through the same memory
position, it implements a handshaking scheme, so that higher layers can identify when
something has changed. This handshaking scheme is only implemented for registers that
are written from the field bus, and is not used when registers are read from the field
bus. As a result, the Modbus uses different read and write registers for the same
parameter.