Need Help!- Alarm 291 Low air volume/pressure durning atc

[Twenty6]

I have a VF-2 and my machine and it is producing alarm 291. This alarm occurs while doing tool changes. The alarm only happens when there is a tool in the spindle while changing tools. The alarm does not happen when there are no tools in the spindle while doing a tool change. I checked the clamp/unclamp switch and they are working properly. I removed cable 890 and 950b from the cable track to see if they were getting shorted out. I ran the cables on the outside of the cable track and ran the machine for a few hours today and the machine alarmed out about once or twice every hour while running. Can anyone direct me of what to check next? Is there anything I overlooked? Has anyone had a similar problem? You can contact me directly at tylerjarosz@hotmail.com if you would like.

[miljnor]

I used to have this problem sporadically, what solved it for me is going to a 3/8" air line and loosing any quick disconnect that was inline.

If you have done that already then ignore me....but its usually a restriction in air flow rate not necessarily pressure (although that can be a factor)

[Bryan33]

I am a Haas factory tech

This alarm is caused by a low volume of air during a tool change (what is means is while you were doing a tool change you did not have enough air pressure to keep the TRP down all the way). You to increase your air psi or add an accumulator tank behind you machine

[Geof]

I solved a similar problem by putting a reservoir tank on the machine side of the regulator, tapped into the 85psi lines.