page 4
Measuring and Displaying
Torque
Note: torque transducers are
delicate pieces of equipment and
can easily be damaged irreparably
unless treated with care.
COMMUNICATION
WITH EXTERNAL
DEVICES
displayed do not distinguish between anticlockwise and
clockwise rotation, i.e. rotation at 2rpm in either direction will
be displayed as a positive value,
anticlockwise rotation will
not be displayed as a negative value. Similarly, if the platen
is rotated two revolutions clockwise, then half a revolution
anticlockwise, 900˚ will be displayed, not 540˚, i.e.
it is the
total accumulated rotation, not the effective rotation which will
be displayed.
Pressing the
[RST]
button (4) will reset the degrees of rotation
displayed to zero.
Torque is measured on a Vortex by a ‘smart’ static torque
transducer mounted on the adjustable crosshead. The
transducer must be connected to an Advanced Force/Torque
Indicator (AFTI) mounted on one of the columns of the Vortex
(see illustration on front cover). The torque transducer is
connected to the 15pin female D-connector on the side of the
AFTI.
One way of causing irreparable damage would be to drive the
base fixture at high speed to a point where the transducer
encounters something ‘solid’. This is a risk when a user is, either
unfamiliar with operating a new test frame, or with the
characteristics of a new sample. It is recommended that an AFTI
to Vortex cable is fitted (see following section) and that a
suitable ‘alarm point’ is set; please refer to the AFTI operating
manual (Part 431-213).
There is an external control port (15pin female D-connector) at
the rear of the Vortex. This display unit interface enables the
Vortex to respond, via the appropriate Mecmesin cable (Part
351-062), to a signal from an AFTI via the 15pin male D-
connector on the top of the unit. With this cable connected, the
Vortex can stop rotating the lower platen when an alarm point
or sample break is detected. For further information please refer
to the AFTI operating manual (Part 431-213).
Some applications require a graphical representation of the test
data – if more than one peak reading is of significance, for
example. Mecmesin DataPlot software can be used to plot
torque values as a function of time, or as a function of angle
