Need Help! with my milling machine
1. The problem is that the Mesa card didn't send 10 volts the the servo amplifier when i set the Rpm
in MDI to 7100rpm wich is the maximum spindle speed the motor can handle
Have you set the pwm scaling to 7100?
The second problem is when i shut down the Pc but have the machine Power still on all Outputs getting true signal spindle brake also, and thats really bad the Z-Axis runs down then.
I think that it might be possible to wire the brake to that you need to set the output to "Low" to release the brake. PCW can probably advise.
Otherwise you might need to use a normally-closed relay, though that does seem crude.
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7I37TA outputs are off unless linuxcnc is running and has commanded them to be on.
If you have a Z axis brake, its control should be wired to a 7I37TA output such that the brake
is only disengaged when the 7I37TA output is on.
7I37TAs should normally get 5V logic power from the FPGA card,
_not_ an external source.
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thanks for the fast answers, i attach my files this may could help.
Have you set the pwm scaling to 7100?
I think so iv'e set the output_scale parameter in the ini to 7100 this should be the same right?
its linked with the " setp hm2_5i20.0.pwmgen.03.scale [SPINDLE_9]OUTPUT_SCALE" hal command
when i change this value the rpm is changed too bu i never get more than 6900rpm is there anything iv'e forgot ?
If you have a Z axis brake, its control should be wired to a 7I37TA output such that the brake
is only disengaged when the 7I37TA output is on.
Yes thats right and my spindle brake is wired on the card and is controlled by Classicladder but when the pc is shut down all outputs switch to true.
so my only way at the moment to provide that is to turn first the Machine power off on the main switch and then shut down the pc with linuxcnc, i know that this should be the standard procedure but sometimes my brain is on holyday and ill switch off the pc first
![:) :)](/media/kunena/emoticons/smile.png)
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Yes thats right and my spindle brake is wired on the card and is controlled by Classicladder but when the pc is shut down all outputs switch to true.
Are you saying the 7I37TA outputs turn on when the PC is turned off?
If so, this indicates some kind of major problem. Do make sure that you are
_NOT_ suppling external 5V power to the 7I37TA, that is the 7I37TA P1
should be unconnected and W1 should be in the up position.
If you cannot get a 10V output from the 7I33TA when the PWM setting for the channel is set to the
PWM scale value, this indicates an electrical problem.
You can check both the PWM value and the PWM scaling via halmeter
To diagnose electrical issues with an analog output, if the PWM value and
scale are set so you expect 10V output and you don't read 10V with a voltmeter:
First disconnect the analog output at the 7I33 card and check the analog output
voltage without a load. if this is still low, check the 5V power at the 7I33TA card
This can be measured at P1. If this is lower than 4.5V you will probably have to
power the 7I33TA from a cable from PC 5V to the 7I33TA's P1
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i have testet the X-Axis too and like u said also no 10 Volts.
now i have to search where the problem is, ill will fowllow your instructions we will see what comes out.
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when i connect the cable i have at full commanded speed only 9,78Volt so i guess its the cable length is the problem how can i compensate the loss of voltage through the cable?
is it possible to get more than 10 volt from the 7337TA?
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If the 7I33TA's 5V is low you will not be able to get the full 10V output
(and it may drop with load as you have noticed)
Also the 7I33 full scale output precision is specified as +-3% so full
scale output on a a given 7I33 may only reach 9.7V (typically they are better than 2%)
Normally full scale range is really not an issue since you don't want a servo
system to get within about 10% to 20% of full scale velocity in normal operation.
That is, if things are correct you really dont ever want the analog output to get higher
than 8V or 9V. This is so that you have "headroom" in both the 7I33TA and the servo
or spindle connected to the 7I33TA.
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one question i have left.
I would like to install an potentiometer for feed override but the mesa 7I33TA is full so i thought i may can do it with the 5i20 cards they should have analog inputs ?
i thought i take an potentiometer an grab 5v from an external power source an adjust with the potentiometer the input voltage to the 5i20 will that work ?
the other option i have an rs232 output at the PC is there a Mesa card for my purposes who would fit?
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