DATREND Systems ES601 Plus, Operating Manual

Page: 152 / 233

ES601 Plus OPERATING MANUAL
7 Computer Control
7.1 Overview of Computer Control
ES601
Plus
provides a communications interface that allows personal computer (PC) software to
control the safety analyzer and acquire measurement data in realtime as safety tests are being
performed. Although a terminal emulation program such as Windows
HyperTerminal may be used to
operate ES601
Plus
in this manner, computer control is more suited to users who intend to develop
their own PC software to satisfy particular testing or documentation requirements. Alternatively,
users may prefer existing third-party software that provides means for instrument control and data
acquisition through simple user-written scripts (e.g. MEBEDO
fu n d am e d ).
When testing leakage, ES601
Plus
saves results in the Test Record for all normal and single fault
conditions enabled by the user in the test setup. However, if the user has enabled supplementary test
conditions ("DUT-OFF" tests; isolated data I/O tests; ungrounded metal part tests), then
ES601
Plus
records only the maximum leakage result observed under the supplementary conditions.
ES601
Plus
computer control allows user-supplied software to acquire leakage data from every
measurement performed, whether the test condition is normal, single-fault, or supplementary.
For computer control, ES601
Plus
is connected to a serial COM Port on the PC. For PC's without a
COM Port, any third-party USB-to-RS232 converter cable can be used, which will allow the user's
software to communicate with ES601
Plus
via a Virtual COM Port (a Virtual COM Port or "VCP" is
driver software which is supplied with the USB converter cable, or which may exist as part of the PC
operating system).
In general principle, the user's PC software begins by opening a COM Port (physical, or VCP for
USB connections). The software transmits a command via the COM Port to ES601
Plus
which
selects and starts a Safety AutoSequence. As each step of the sequence is completed, ES601
Plus
transmits measurement results to the PC as a string of formatted ASCII text containing data fields
delimited by the comma character (CSV data format). Upon conclusion of the sequence, ES601
Plus
sends an "END" message to the PC. Optionally, the user's software may then issue another
command to cause ES601
Plus
to return a formatted Test Report document containing the
measurements recorded by ES601
Plus
during the test. The format of this document is the same as
that obtained when printing a previously-saved Test Record to either the Centronics or RS232 port
of ES601
Plus
(see Section 4).
Computer Control/Chapter 7
#
Page 133