| When I start PL
Pilot there does not seem to be an option to work offline
(without a drive connected)? |
 |
Although the first screen you see refers to "countdown
to auto online" and "go online now", PL Pilot will still work
if you don't have a drive connected. Hitting the "go online
now" button or waiting for the countdown timer to expire will
launch PL Pilot anyway, although of course you will not see
any values in any of the screens unless you call up a recipe. |
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| The help files
do not seem to be present on my installation disk. |
|
The
"help" menu on the Windows task bar is referring to those
files which are part of the overall SpecView package, rather
than PL Pilot which is an application running within the overall
package. These help files are not on the installation disk.
However, PL Pilot specific help is available from the Entry
Menu screen via a button on the top right hand side of that
screen. |
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| What is the purpose
of the "defaults" and "range" buttons at the top of most screens? |
|
These two buttons call up "read only" lists in the
form of a dialogue box showing factory settings and permissible
range of every drive parameter. Although this dialogue box
is equipped with a "send" button, it has no effect. The lists
are for reference purposes only, if you want to restore a
drive default setting you have to change the value in the
normal way either via the drive MMI or the PL Pilot parameter
entry dialogue box. |
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| Why can't I see
my saved recipes in Windows Explorer? |
|
When PL Pilot saves recipe files, it does not save
them with a name such as the description you may have given
when in "recipe management". Instead it just increments the
file extension for every new recipe saved. Furthermore, it
does not always save the recipes using names relating to the
screen you happen to be in - if you were saving a recipe in
the "Total Recipe" screen for example it would be saved as
Recipe7.Rxx where xx is the incremented number, R00 being
the "default" recipe and R01 would be your first saved recipe.
If you have a number of saved recipes and are not sure which
one is which, you can right click on a recipe when in Windows
Explorer and open the file with Word Pad or a similar application.
You will be able to see the description you gave the recipe
at the start of the displayed data. |
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| I have saved a
recipe, but some of the changes I have made do not transfer
when I load them to a drive? |
|
It
is important to remember that the recipe system only saves
parameters that are contained within the screen you happen
to be on at the time. For example if you were in the "calibration"
screen and saved a recipe from there, the only items contained
within that recipe (which incidentally is saved as Cal.Rxx)
are those you can see on the calibration screen. If you had
also made changes to the "stop mode ramps", those changes
would not be automatically saved unless you also save the
recipe in that screen. This means that you need to transfer
both recipes to the drive if you want all the changes made
to be transferred. However, any changes you make on any screen
will also show on the "total recipe" screen, as long as you
are working on line with a drive connected. (If you are working
offline a different method is required, see later notes.)
Therefore, the thing to do is to go to the "total recipe"
screen and save the recipe from there as it will contain every
parameter. |
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| I am working offline,
and I only want one recipe to cover all my changes? |
|
When working off line you can of course create multiple
recipes to cover different screens, and if possible this is
the easiest way to work - the individual screens group parameters
in a more orderly fashion than the "total recipe" screen.
However, if you only want one recipe to cover changes in more
than one screen, say in "calibration" and "stop mode ramps"
there is no alternative but to work in the "total recipe"
screen. As this screen contains all the drive parameters it
is not so easy to navigate, but you can use the Windows zoom
and scroll functions. |
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| I have called
up a recipe when working offline - but as soon as I exit the
recipe management box the values disappear? |
|
This also occurs if you call up a recipe when working
online, except when you are working online you are able to
transfer the recipe to the drive by hitting the "send" button
- PL Pilot is of course a means of inspecting and altering
the contents of drive RAM. When you are working offline there
is no drive RAM to work with, so the only option is to use
the "hide this box" rather than the "exit" button. |
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| How do I switch
between screens when working offline with recipes? |
|
This really follows on from the last question -
once you have used the "hide this box" button, you are not
able to switch screens as PL Pilot locks out the buttons.
If you want to switch screens you have to once again call
up the recipe management box and hit the "exit" button. A
warning box appears if you have not saved the recipe. |
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| Do I need to use semiconductor
fusing? |
|
Unconditionally yes. This is the only way to protect
the drive bridge in the event of a fault anywhere in the system,
and it is a warranty condition for the drive. There are certain
breaker types on the market that are claimed to be fast enough
for semiconductor protection but we have yet to find one that
affords the same protection as a correctly rated fuse. Whilst
on the subject it is worth pointing out that the maximum current
rating of a fuse is of secondary importance as long as it
is large enough - the drive current limit and stall algorithms
are sophisticated enough to protect against damage by long
term overload. The important part of the fuse rating is its
I²T rating. Expressed in A²S (amps squared seconds)
this is a measure of energy let through and the maximum allowable
for any drive is given in the product manual fuse rating table.
Essentially, if an I²T rating is not given in a manufacturers
fuse specification details it is unlikely to be adequate -
even if an alternative name such as "superfast" is used in
the manufacturers description.
The above comments apply to fusing in the a.c. supply and
the d.c. output to the armature, where a d.c. fuse is fitted.
A.c. supply fusing is mandatory in all cases, d.c. fusing
must also be employed in systems capable of regenerative current.
With regard to the d.c. fuse, particular care should be taken
to ensure that it is d.c. rated - the fuses used in the a.c.
supply may not be, even if their I²T rating is correct. |
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| |
| Can I use an external emergency
stop system to interrupt the supply to the main contactor
coil? |
|
As
far as the safety of the drive is concerned (and our warranty)
it is crucial that the drive controls the main contactor without
any external interference. Any emergency stop system should
be connected into the coast stop input, terminal 34. This
will allow the drive to safely cease current flow prior to
opening the contactor - in about 100 milliseconds. However,
should local safety codes mandate that the contactor coil
supply can be interrupted directly by emergency stop thus
not relying on the drive control electronics, you must put
an auxilliary contact of the contactor in the run input on
terminal 31 - at least that way the drive has a reasonable
chance of shutting down current flow prior to the bridge supply
being discontinued. In addition, there are some sites that
insist that all supplies to the drive are interrupted under
emergency stop conditions. This of course means that the line
to neutral control supply also disappears. This is less of
a problem than you might suppose because the digital drive
is designed with a power supply that is self supporting for
a short while after power off whilst it does certain housekeeping
tasks. In effect there is very little difference to the drive
if you remove all supplies at the same time as long as you
have adhered to the above recommendations concerning the run
input. |
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| |
| I have only one contact available
for starting and stopping the drive - should I use run or
start or coast stop? |
|
The best way
is to permanently tie run and coast stop to 24V and use your
contact to switch the start input, terminal 33. Under these
circumstances the drive has control over the contactor, ramp
to stop time etc. It is definitely not a good idea to tie
the three inputs together and use one contact for all three,
for example. |
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| |
| Why can I not change GOTO or
GET FROM settings whilst configuring the drive? |
|
Probably because you have not enabled configuration.
Go to CONFIGURATION, ENABLE GOTO/GET FROM and set it to enabled. |
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| |
| I have made configuration changes
but they have not taken effect? |
|
The
drive does not update the block diagram until configuration
is disabled. Go to CONFIGURATION, ENABLE GOTO/GET FROM and
set it to disabled. |
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| |
| How do I get an output that tells
me the drive is up to speed? |
|
This can be taken to mean one of two things - the
speed demanded has not yet been reached because the drive
is imposing a ramp on the demand and/or the drive is in current
limit whilst accelerating (or decelerating). In either event,
an appropriate PIN is available. The technique is to go to
CONFIGURATION, DIGITAL OUTPUTS, select whichever digital output
you want to use and set the GET FROM to the appropriate PIN,
either 35) RAMPING FLAG or 141) AT CURRENT LIMIT depending
on need. The default settings already configure 35) RAMPING
FLAG on to digital output DOP2 (terminal 23) as standard. |
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| |
| How do I get an output that tells
me the drive is healthy (or ready)? |
|
The
digital output on terminal 24 (DOP3) is a drive healthy signal
in the default settings. We assume that the drive cannot be
anything other than healthy if the START command has not been
satisfied, in other words if the main contactor has not been
energised and there is no power supply to the bridge on L1,
L2 and L3. Certain applications require this signal to be
conditional on START, so that the healthy output is low if
the main contactor has not been energised. The solution is
to use one of the multifunction blocks as an "and" gate looking
at the healthy and drive start PINs. The following assumes
you wish to still use DOP3 as the healthy output and also
that multifunction 7 has been chosen for use as the "and "gate
although either of the 8 multifunction blocks could be used.
Go to APPLICATION BLOCKS, MULTIFUNCTION 7 and set 566) MULTIFUN7
MODE to AND GATE. Set 557) MULTIFUN7 OP SEL to ENABLED, GET
FROM to 698) HEALTHY FLAG and AUX GET FROM to 166) DRIVE START
FLAG. The GOTO needs to be set to one of the digital staging
posts, say 299) DIGITAL POST 4. You now need to change the
default set up of DOP3, so go to CONFIGURATION, DIGITAL OUTPUTS,
DOP3 SETUP and set the get from to 299) DIGITAL POST 4. |
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| |
| How do I do field weakening? |
|
This question is usually accompanied by a statement
to the effect that it has proved difficult and/or time consuming
in older drives. With the digital drive it is simple. Providing
you have set the BASE SPEED and TOP SPEED parameters correctly
in CHANGE PARAMETERS, CALIBRATION and remembering that you
must be using either tachogenerator or encoder feedback -
field weakening cannot work with armature voltage feedback
alone, all you need to do is go to CHANGE PARAMETERS, FIELD
CONTROL, FIELD WEAKENING MENU, FIELD WEAKENING ENABLE and
set it to enabled. This will be adequate in most cases. Certain
motors require armature current profiling to help commutation
in the weak field region, and the motor manufacturers details
should give this information if appropriate. If this is the
case the relevant parameters are found in CHANGE PARAMETERS,
CURRENT CONTROL, I DYNAMIC PROFILE. |
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| |
| How do I switch between two signals
using a digital input? |
|
Each digital input has two PIN that can be connected
to any parameter, analogue or digital, within the block diagram.
For example, if you wanted to switch speed demand inputs for
local/remote speed control, using UIP2 for one input and UIP3
input the other with DIP2 controlling which was selected it
is done as follows: -Go to CONFIGURATION, UNIVERSAL INPUTS,
UIP2 SETUP and set the UIP ANALOG GOTO to 400) Block disconnect.
This disconnects the default connection from UIP2 to the speed
loop. Go to CHANGE PARAMETERS, SPEED REF SUMMER and set 67)
SPD/CUR RF3 RATIO to zero. This is because the connection
from UIP3 into the drive speed/current loop is "hard wired"
internally and cannot be disconnected as you did with UIP2.
Therefore you have to set its ratio to zero instead. The next
task is to connect the two UIP inputs to the digital input,
and then connect the digital input analogue output into the
speed loop. Connecting its analogue output is straightforward.
Go to CONFIGURATION, DIGITAL INPUTS, DIP2 SETUP and set its
GOTO to 63) SPEED REF 2. Connecting the two values that DIP2
will switch between is slightly complicated by the fact that
we need to connect two PIN together - because the PIN involved
do not have GOTO or GET FROM. The solution is to use jumpers.
Go to CONFIGURATION, JUMPER CONNECTIONS, JUMPER 1 and set
its GET FROM to 150) UIP2 ANALOG MON and its GOTO to 312)
DIP2 IP HI VALUE. Similarly, set JUMPER 2 GET FROM to 151)
UIP3 ANALOG MON and its GOTO to 313) DIP2 IP LO VALUE. Incidentally,
the above description makes use of a direct (non-ramped) speed
input. If you wanted to apply the ramp controls which by default
are applied to the input on T4 (UIP4) the technique would
be to disconnect UIP4 by setting its GOTO to 400) Block disconnect
and taking the DIP2 GOTO to 26) RAMP INPUT instead of 63)
SPEED REF 2. |
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| |
| I have changed 37) JOG SPEED
1 to a negative amount but the drive still jogs forward? |
|
This is commonly because of a misunderstanding regarding
the use of the jog input on terminal 32. For jog to be used
T32 is taken high but not T33 (Start). If you take them both
high, you are actually running under 39) SLACK SPEED 1, see
the truth table in the JOG CRAWL SLACK block diagram. The
solution is to change the external sequencing so that jog
and start are mutually exclusive or use 39) SLACK SPEED 1
as your jog speed reference. |
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| |
| How do I scale the analogue outputs
if my metering system is not the same as the drive outputs? |
|
The analogue
outputs have a maximum output of + or - 11.3V at + or - 5mA
with 10V representing 100% by default. Each analogue output
has a divider , offset control and can be set to rectified
or bipolar. For example AOP1 is by default set to 715) SPD
FBK % UNF, which is the unfiltered speed feedback at + or
- 10V = + or - 100% speed. If your metering system requires
this output to be 5V at full speed in a single direction only
you would go to CONFIGURATION, ANALOG OUTPUTS, AOP1 SETUP
and set 251) AOP1 DIVIDER to 2.0000 and 253) AOP1 RECTIFY
EN to enabled. The only analogue output you cannot do this
to is T29, the armature current output. It can be set to rectified
or bipolar but cannot be scaled - if you need a scaled version
of armature current you will have to use one of the other,
scaleable, analogue outputs having set its GET FROM to the
appropriate PIN, usually 134) ARM CUR % MON. |
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| |
| How can I check that I have not
made a mistake during configuration? |
|
It is of course
possible to forget to disconnect a connection that you are
intending to use for something else - for example by setting
the analogue output GOTO of UIP2 to 26) RAMP INPUT whilst
forgetting to disconnect the default input to that pin from
UIP4. The drive will tell you there is a problem when you
try to set ENABLE GOTO,GETFROM to disabled after making the
change. The error message is !!!!!!ALARM!!!!!!! GOTO CONFLICT.
It will not tell you what the conflict is, for this you have
to go to CONFIGURATION, CONFLICT HELP MENU, where you will
be able to see how many conflicts there are and on which PIN. |
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| |
| How do I perform forward/reverse
with only a single polarity speed reference? |
|
There are
many ways to do this within the PL/X but our preferred method
is always to perform any sequencing external to the drive
if practicable as doing so keeps as many drives as possible
in default configuration. In this instance, as a contact would
have to be used to tell the PL/X to reverse this contact may
as well be used to switch the top of the setpoint pot (if
used) between + and - 10V. If an external speed reference
is being used the method is to switch the signal between two
speed demand inputs and set the scaler of one of them to -1.0000.
However, if it is necessary to use a digital input for the
purpose - perhaps because that is how it was done on previous
occasions with other drives, one solution is as follows (assuming
that DIP1 is being used for the switching and that UIP4 is
used for the speed demand input):-
Go to CONFIGURATION, ENABLE GOTO,GETFROM and set to ENABLED.
Go to CONFIGURATION, DIP1 (T14) SETUP, 310) DIP1 IP HI VALUE
and set it to -100.00%
Go to CONFIGURATION, DIP1 (T14) SETUP, 311) DIP1 IP LO VALUE
and set it to 100.00%
Go to CONFIGURATION, DIP1 (T14) SETUP and set its GOTO to
342)UIP4 CAL RATIO.
Go to CONFIGURATION, ENABLE GOTO,GETFROM and set to DISABLED.
Don't forget to do a PARAMETER SAVE once you have finished,
and please also see a later note regarding parameter unit
values for an explanation of how the PL/X treats numbers.
|
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| |
| How do I perform encoder based
speed ratioing? |
|
At present
the PL/X is equipped with only one set of encoder inputs,
so it is not possible to ratio a PL/X in encoder feedback
to another encoder. It is however possible to ratio a PL/X
in encoder feedback to another PL/X in encoder feedback via
a speed demand transmitted through the serial link when in
REFERENCE EXCHANGE mode. The technique is as follows:-
1) Master drive.
Go to CONFIGURATION, ENABLE GOTO,GETFROM and set to ENABLED.
Go to SERIAL LINKS, RS232 PORT1, 188)PORT1 FUNCTION and set
to REF EXCH MASTER.
Go to SERIAL LINKS, RS232 PORT1, REFERENCE EXCHANGE and set
its GET FROM to 709)MOTOR RPM %
Go to CONFIGURATION, ENABLE GOTO,GETFROM and set to DISABLED.
2) Slave drive.
Go to CONFIGURATION, ENABLE GOTO,GETFROM and set to ENABLED.
Go to SERIAL LINKS, RS232 PORT1, 188)PORT1 FUNCTION and set
to REF EXCH SLAVE.
Go to CONFIGURATION, BLOCK OP CONFIG, REF EXCH SLAVE GOTO
and set it to 331)UIP3 IP OFFSET.
Go to CONFIGURATION, ENABLE GOTO,GETFROM and set to DISABLED.
It is now possible to set the master/slave speed ratio by
going to CHANGE PARAMETERS, SPEED REF SUMMER and setting 67)SPD/CUR
RF3 RATIO as desired. It is also possible to change the sign
of the speed demand in CHANGE PARAMETERS, SPEED REF SUMMER,
66)SPD/CUR REF3 SIGN. Further scaling and limiting are possible
using 332)UIP3 CAL RATIO, 333)UIP3 MAX CLAMP and 334)UIP3
MIN CLAMP in CONFIGURATION, UNIVERSAL INPUTS, UIP3 (T3) SETUP
if needed. |
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| |
| I want two stop times, normal
and E Stop? |
|
It has proved
a popular request to have the facility for two stop ramp times
- one for normal production stops and a very much faster one
for emergency stop. This is easy to do, but before explaining
how to do it a word about the use of "emergency stop". There
are various differing opinions and safety legislations about
emergency stopping, and we consider emergency stop to be the
same as coast stop - in other words removal of power from
the motor without relying on the drive electronics as far
as possible. This of course does not stop the motor any faster
than the natural coast down time of the entire system, so
we recommend the use of additional braking techniques external
to the drive if a quicker stop time than this is required.
If you are considering using the drive electronics alone to
stop the drive quickly under emergency stop conditions you
should be aware of two points - firstly that the quick stopping
time achieved will not occur in the event of a drive failure
and secondly that you may be violating local safety codes.
On the assumption that you are happy to use the drive electronics
to control the emergency stop time, the technique is to use
a digital input to set the stop mode ramp time. In addition
to your normal sequencing you need to arrange for one of the
digital inputs to be high for "normal" stop, low for "emergency
" stop. Having done this, configure 56)STOP MODE RAMP as follows.
(I have assumed you will be using DIP1 - you can use any digital
input (or universal input) in the same way.)
Go to CONFIGURATION, ENABLE GOTO,GETFROM and set to ENABLED.
Go to CONFIGURATION, DIGITAL INPUTS, DIP1 (T14) SETUP and
set 310)DIP1 IP HI VALUE to whatever you want your normal
stop ramp time to be. For example, 1.00% gives a stop mode
ramp time of 10.0 seconds, 3.5% gives a stop mode ramp time
of 35 seconds. For an explanation as to why the values are
not consistent see a later FAQ.
Go to CONFIGURATION, DIGITAL INPUTS, DIP1 (T14) SETUP and
set 310)DIP1 IP LO VALUE to whatever you want your emergency
stop ramp time to be. For example, 0.10% gives a stop mode
ramp time of 1.0 seconds. The minimum time settable is 0.1
seconds.
Go to CONFIGURATION, DIGITAL INPUTS, DIP1 (T14) SETUP and
set its GOTO to 56)STOP RAMP TIME. Go to CONFIGURATION, ENABLE
GOTO,GETFROM and set to DISABLED.
Don't forget to do a PARAMETER SAVE once you have finished.
|
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| |
| Why do I sometimes have apparently
differing unit values if setting a parameter from another
parameter? |
|
Irrespective
of any engineering units or decimal points applied to a given
parameter, the PL/X treats the parameter as a pure number
with signing as far as the MMI is concerned. As an example
if you wanted to set 342)UIP4 CAL RATIO (which has four decimal
places and no engineering units) from 310)DIP1 IP HI VALUE
(which has two decimal places and is expressed in %), strip
the decimal point and ignore the units in order to arrive
at the required value. In other words, if you wanted 342)UIP4
CAL RATIO to have a value of -1.0000, 310)DIP1 IP HI VALUE
would need to be set to -100.00%. |
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