Application examples
COMPAX-M/S
Speed control mode
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11.1.6 Speed control mode
Application:
A centrifuge for manual operation should be operated by an operating mode switch. The centrifugal process
should either be run at a permanently set speed or the test tubes should be removed, one after another,
through the removal aperture. The shutter on the removal aperture must only be able to open when the
centrifuge is at a standstill.
Design and wiring up of the digital inputs and outputs:
light
barrier
opening
shutter
test tube
+24V
light
barrier
I10
I7
COMPAX
operating mode:
0 = remove
1 = centrifuge
I8
I9
O7
shutter
+24V
+24V
locking
Function:
The first event after COMPAX has been started is the setting of the accelerating and braking time 10s
(N001). A check is then run to find out whether the shutter is closed (N002). If it is not closed, the interlock is
opened (N003) and the system waits until the shutter is closed (N004). If the shutter is closed, the interlock is
also closed (N005). The interlock is checked for safety reasons (N006). The operating mode switch is then
queried (N007).
If this is set to "Removal", the speed is set to 0.1 % using N008. The system waits until the light barrier is
activated by a test tube (N010). When this occurs, the speed is set to 0 (N011) and the interlock is opened
(N012). The shutter can now be opened to insert or remove a test tube. COMPAX monitors the opening and
closing of the shutter (N013 / N014) to lock this again after the closing (N015 / N016) and to return to the
operating mode query. If "Removal" is still set, the centrifuge is turned further to the next test tube. (N009
ensures that once the speed has accelerated to 0.1% (N008), the system waits until the previous test tube
no longer activates the photoelectric barrier.)
If the operating mode switch is set in the "Centrifuge" position, the centrifuge is accelerated to 100% within
10s (N018). This speed is retained until the operating mode switch is set to "Removal" (N019 / N020). Then,
the centrifuge is decelerated to 0.1% (N008) and stops at the next test tube. The test tubes can then be
removed one after another.
