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problem is to start the DS9000 and put it into TACH mode (push the TACH key). If it reads anything
other than "0" and the motor shaft is not turning then the DS9000 is picking up noise!
7.2.7
MASTER – FOLLOWER OPERATION
A).
When having problems with speed and or position "lock" remember to use the TACH feature
of the DS9000. For example in a follower mode if the follower isn't behaving properly
(following speed) turn dip switch 5 to the OFF position (down) and push the TACH/REF key
while running to illuminate the TACH LED. You should see the speed of the MASTER
reference signal on the display as it is scaled by SCF1/SCD1 values. Verify it is the value you
would expect to see with the master running at a known rate. Also verify that there is a linear
relationship from top speed through less than 5% speed. If this speed is not correct or it
fluctuates then you should expect the follower to do likewise, i.e. the Master is probably the
problem. Check the follower speed switch 5 on (up). It is scaled by SCF0/SCD0.
B).
In most cases when operating in the follower mode it is recommended to run with dip switch
2 on (up). This will cause the follower to follow the speed of the master but not the position.
This reduces overshoot and undershoot problems that are caused by the position loops' need
to resolve position errors encountered during acceleration and deceleration. Open loop
position is not an error condition while running in the follower mode. It is recommended for
most follower applications that do not need to track the feedback signal.
C).
When having problems as a Master controller turn dip switch 2 ON putting the unit into open
loop. The output will then be a scaled 0-10V signal relative to your SCF0 value and the
setpoint setting. If the setpoint (PS1 for example) is at 900 and SCF0 is set to 1800 then there
would be – 5V out of the DS9000 and the drive should be going ½ speed. If the drive has an
offset control then it can be set to half speed with this setting. Also you can verify the speed of
the motor by looking at the tach signal (push TACH/REF to illuminate TACH).
D).
It is important that the DS9000 be installed on a line that is free of severe line transients,,
brownouts, dips, or surges. An isolation transformer (less than 50VA) is recommended where
severe line noise exists. Also ALL relay coils should have an appropriate snubber installed at
the device, an RC snubber (0.1 microfarad luf with 100 ohms) for AC devices or a diode for
DC devices.
E).
The feedback device (and the appropriate dip switch 3 or 4) needs to have a signal that goes
positive and negative at least 50 mV (depending on frequency). If your sensor is this type
("mag" sensor for example) then sw #3 or 4 should be down. If your sensor goes to 0V
<signal< .7V for a "low" and 2.5 <signal< 5.7V when high then dip switch 3 (or 4 for Master
reference) needs to be up (ON). This type of device is required for low speed operation.
If you are having intermittent problems with the DS9000, erratic behavior or periods of
uncontrollability please go through the above tests. If these tests do not point you in the direction of a
solution then contact your distributor or Superior Electric applications with the following
information: A complete list of the programmed parameters, a hand sketch of how the system is
wired, a description of the feedback sensor(s), detailed description of the problem including time of
day failure info, time of machine operation cycle (if applicable), types of failure (complete lock up,
loss of control, etc.) frequency of failures, etc.
Superior Electric has available a small test board that will test both the Master and follower
capabilities of the DS9000 in order to verify the units integrity. Please contact Superior Electric
applications for information on this test card.
8.0
PARAMETER CODE/VALUE WORKSHEETS
Once the system parameters have been determined to fit your applications, complete the following
worksheet to keep a permanent record of the parameter values and dipswitch positions. This can help
prevent system downtime in case of an accidental parameter or dispswitch change.
40
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Troubleshooting
