Alarms

[jonunder]

Quick question about alarms and the MASSO. After an air low alarm is tripped, it doesn't seem to automatically clear. So far I have been able to clear it by homing, but is it possible for it to clear automatically once air pressure is restored? Is there another way to clear the alarm instead of homing every time?

I recall seeing similar behavior in the axes alarms also. I was able to clear the axis alarm by homing the machine, but the MASSO seemed to ignore if the alarm was actually fixed. If the servo alarm still existed, that axis wouldn't move, leading to the potential for a crash. I think this creates some usability issues for a user. The SureServo drives have a servo reset capability that can clear some alarms, but not others. So the user may attempt to use the servo reset button, but without feedback from the MASSO, they would have to go to the back of the machine and open the NEMA box which is considered a safety violation. This forces the user to reboot the machine for each axis alarm.

 

[masso-support]

each alarm can be handled in a different way depending on how the users want it, till now in most of the critical alarms the machine needs to be homed to clear but we can look into this. So at this stage are you looking into the air low alarm only or others too?

 

[jonunder]

I'm not an experienced machinist, so I would be interested in other people's opinions to back up my thoughts. I would like to see the air alarm go away if the signal returns to nominal without homing. It seems that the alarm goes away when homing, even if the alarm is still active.



As for the axis alarms, I would like to see the alarm go away if the signal goes to normal and then require homing. This way there is feedback to the user to show that the alarm has been in fact fixed. Some servo alarms require power reset, while some can be fixed via a reset line.

 

[masso-support]

sure, let's wait for some time for other users feedback on this topic and we will make a logic review plan for each alarm.

 

[jonunder]

Sounds good, what is the best way to get feedback about it?

 

[al]

on other controllers , things like low air pressure , low way oil , low coolant , door open etc - these put the machine in a feed hold condition with a indicator light or message on the screen of what tripped the error , the operator can rectify the problem and press cycle start to continue with running the program , no rehoming or start from beginning of program required.

if I run into a limit switch it generates a over travel error and shows which axis and +, - direction then I go into jog mode and use hand wheel to move off tripped switch error goes away and its ready to machine again no rehoming

if I e-stop or have a power failure or a drive / motor failure or spindle problem then we have to fix / clear error and cycle power and rehome the machine

 

[masso-support]

thanks @al and please keep your feedback coming in this topic.

On the MASSO G2 the memory was limited and we could not add detailed message details but can definitely add this to the G3 controllers, will definitely make troubleshooting for the user much easier.

 

[airnut]

I for one would also like to see at least the air alarm reset automatically when air comes back on. This feature was not even on this machine in its previous life.

In my case I spent most of the day trying to figure out what I did wrong. I thought I had it wired wrong, I changed it and it still did not work like I expected. Only when decided to try the on / off buttons and recycled the Masso with the air on did the alarm clear.

This is one of those little details it would be nice to know about in your manual. It seems like we have to guess on what is supposed to happen most of the time. Makes it hard on us builders trying to second guess what the program does or does not do for each input/output.

Been thinking about this and I suppose the thinking may be that the air is what powers the spindle brake, so perhaps it might be considered a quasi safety issue. That is, forcing a reset to be able to use the machine is a safety fix thing. I like to protect myself, so my vote is automatic reset when the switch is cleared. This will be a all new machine when and if I get it done so I can live with it either way as long as I know what to expect.

I haven't got to the X,Y,Z or spindle alarms yet. Perhaps you have a suggested routine published for those as well? Again its all in knowing what to expect.

Regards,

Steve

 

[MaccaRnD]

Can multiple Drive alarms be wired to the same input, so when any one is triggered the one input is all that s required to Alarm Masso?. A closer inspection of the drives would tell you which is at fault as most have a multi colour LED indicator for status.

I don t think I would have enough space for each drive to use its own input. I m only in the wiring stage at the moment and after culling down the required outputs and inputs I only have one or two of each spare.



With Clearing errors it would be good to be able to Override the Alarm ie hold a button down while rectifying the issue.

I ve had to do this multiple times on industrial machines. (hopefully I didn t miss it if Masso can already do that).

An Alarm reset button or sequence would bo good to be able to just click rather than having to do a full machine re-home or power down/restart.

 

[zombieengineer]

@macarms

What kind of drives are you using? (Vendor & Model)

If the drives have a transistor output it might be possible to wire all the outputs together with a pull-up/down resistor.

Otherwise you may need to use Diode Logic to connect the alarm signals together. Diode logic would require one diode per drive plus a pull-up/down resistor.

 

[MaccaRnD]

@zombieengineer

@masso-support

XYZ are DMM DYN4 -T01A2 AC Drives , hoping to use the DYN4 drives for the other Axis, but I won t have those servos until next week, to be able to check compatibility.

what would be the best way to wire the Drive Alarms togeather, (limited fir space with the amount or inputs that the machine has) would the resisters need to change, Breezy said it s possible to connect them all through one alarm input. I m just not sure of the correct way to wire them all up together, with how the resisters would need to be used. Any help would be great thanks.

Mac

 

[zombieengineer]

@macarms

Manual for your drive - Output is an optocoupler transistor switching to ground (page 13), this is a simple wiring problem not requiring diodes.

Connect all the ALM outputs together to a single MASSO Input with a single 5.6K? pull-up resistor. When there is no servo motor problems the input should be high (the input needs to be inverted from the F1 screen as I believe the motor alarm input is error when high).

 

[MaccaRnD]

Thanks @zombieengineer , I’ll try that and hook it up and see how it goes

 

[RonFinlay]

DMM Tech AC Servo + Masso G3: Z axis Servo Alarm faults the drive, immediately, every time. I have a floor standing mill, so Z is the knee. 750 W AC servo with brake, belt drive to the Z knee screw. The drive faults so often, it's useless. Only recourse is power cycle the drive, home and sometimes within seconds, just sitting there, doing nothing but holding the position, the drive faults. The only faults the DMM Tech interrogation software shows are lost phase and overheat. Each drive has its own 5K6 resistor to each alarm input. Could it be the Masso is telling the drive to fault and stop the motor from being able to move, or the drive faulting and telling the masso to indicate this? Everything works fine, manual jog, push buttons or Masso screen... and then the drive faults. Replaced motor and drive and immediately, same issue. Wiring seems pretty simple, pulse and direction alarm, ground etc from the drive's DB25 to masso. Relay for the brake circuit is all fine. 8 months of this and no clue what else to check. If there's another place on the forum for this, please let me know. Now, a $15K boat anchor. Argh !!!

 

[tmtoronto]

Have you also reached out to the DMM techs?
I have heard good things about their support.

Not downplaying your understandable frustration, or that you are asking the experts here - they also provide excellent support.

 

[cncnutz]

The alarm signal is one way only from the motor to MASSO. MASSO does not alarm the motor. The motor tells MASSO that it has an alarm.
Cheers Peter

 

[RonFinlay]

Thanks Peter for the one way aspect. I really appreciate your quick reply. I also figured as such. So, as I'm assuming, the motor draws a whopping 1 amp, hardly much. The drive overheats, and sends an alarm to Masso, and it locks things down for safety. The motor is belt driven to the Z ball screw at 2:1, so twice the torque and still, only draws 1 amp of wall power while lifting the knee (+saddle + table+ vice). Doesn't sound like it's labouring and the motor doesn't, can't heat up in only 30 seconds and it's cool to the touch. It happens just sitting off the home sensor. Just sitting, not moving the knee at all. I expected more current - 5-10 amps for 750 Watt motor. Not even close, ever.

Drive settings are done by the DMM Tech auto tuning software routine and the Z axis barely makes it to the end and the drive faults.

Can't imagine it's too small a motor - at one horsepower !!! Hoping someone else has experience as so far, DMM has not offered anything. I do appreciate this forum and hope to contribute as I learn and can share.

I'm going to remove the belt, and all load and see if the motor heats up, just sitting there by itself.

Sadly, DMM Tech has been completely non communicative. I don't know why. The only person I have there is Stephen. I have emailed, phoned, texted, sent videos and only last week (July 27, 2024) did the replacement motor and drive arrive, only to have the exact same situation happen. Not knowing his personal life situation, and wanting to be as respectful as possible, but, it's been since December 2023 that I've had this issue since Day One of powering up the drives after months of wiring the whole control box. Certainly no small task. Amazingly, X and Y work fine - same motors (without the brake), same drives, ball screw pitch. Just can't figure this out.

 

[tmtoronto]

It is unfortunate to hear that the DMM communication has been slow and unable to solve the issue.

What pulse rate (kHz) do you have the Z axis set at?
What pitch is the Z axis ballscrew?
Do the DMM drives have the option to control the brake? How do you have the brake wired?

 

[RonFinlay]

DMM has started to respond a bit today, so there's hope. I hope they'll healthy and OK. you never know these days.

As for your comments TMToronto (Ontario !!! So glad as I'm in Toronto, too). No idea about pulse rate. It's a servo not a stepper, so not sure how to know that. All I know is the drive controls the motor and Masso provides step and direction. I'll have to check for this.

Z ballscrew is 2505, so 5 mm pitch, geared 2:1 in favour of twice the motor torque applied to the ball screw. Mass of the table, knee, saddle and all is estimated at 250 pounds. (https://www.busybeetools.com/products/knee-mill-vertical-craftex-cx-series-cx603.html) to see the mill with its 8 x 30" table for reference.

Brake is controlled by the drive, via a relay board (not Masso due to polarity). I built that with indicator LEDs and they work perfectly: ON = brake released and off = brake on. Turns out, when all is well, the brake is released as soon (milliseconds) as the drive has control of the motor and stays released, until loss of power. So, even if just sitting all day, doing nothing, the motor is holding the belt/pulley drive/screw, so it won't rotated as to low friction or vibration. I thought the brake would go on and off like a car in traffic, but, it's only there to hold the table when the power is off and motor can no longer do that. Still, it faults just sitting there. DMM is redoing the size calculations, but feels 750 W is plenty of motor for this small mill. I did remove the belt, and run the motor, via Masso screen, external pushbuttons and every thing works perfectly, so we are 100% sure it's not a wiring issue. (!)

Brake is wired from brake output pin (BKO pin 19) to my relay board. Brake signal is generated by the drive when it has control of the motor. Masso only gets the alarm signal when a fault occurs, as Peter so kindly said, it's a one way, drive to masso, not masso to drive communication. Point is we know the brake is not on, dragging. Assured that way back during a bench test to test my relay board.

 

[RonFinlay]

Also re pulse rate. There are two error states when monitored by DMM tech software - overheat and lost phase. I tested the motor on the bench and when switching from CW to CCW at 3000 rpm, clearly, it messed up and faulted lost phase. I will never use it past 1-200 rpm to lift the mill knee, but that's how I know at my slow speed, it's not a lost phase, pulse rate thing. Also, apparently, the drive uses the encoder feedback to ensure position before issuing the next pulse, so pretty impressive eyeballs.