Yes tommy but in a multi bit change scenario that means the old save each toolpath to a different file, precluding any and all use of the ATC. That is not what I thought I was purchasing.
Until I get the ATC setup correctly, I need to do manual bit changes 
. It’s installed on the spoiler board, but I still haven’t found the correct (and complete) instructions on setting it up. I followed the instructions in the Onefinity manual along with the video in the link they provided. However, those instructions are out of date with the newer MASSO firmware. I found a video from Masso, but they were incomplete. It only described the change in wiring to the controller. Anyway, when I have more time, I will reach out to Masso and RapidChange and try again. For now, I just need to be careful so I can continue to count to 10 with my fingers. 
Since the symptoms are the same, I’d bet you’re right. EMI was a quick & easy explanation. None of my interactions with either OF or Redline before I gave up ever mentioned checking voltage. It seems there was some clever support person who dug deeper and found this.
Of course (like the change to the recommendation to attach a grounding wire from the HMI to the machine frame), no general notice has gone out to owners about this problem. If you’re not in the forum regularly and read everything, you’d never know. It’s like being in top-secret double probation.
I’m going to start using this as a generic excuse for EVERYTHING. 
- Sorry I didn’t make it to your party, but an EMI issue came up.
- This code change is delayed due to an EMI issue.
- I sent the payment last week. It might be delayed due to an EMI issue with the post office.
- I’d really like to come and help you move, but we’re dealing with an EMI issue at work.
remember only two things are certain death and EMI.
Hello All!
We have found the issue and have a resolution! Please see below!
Redline Spindle Technical Bulletin VFD Over-Voltage Fault 4/29/26
Redline CNC Technical Bulletin
Subject: VFD Over-Voltage Fault — Root Cause Identified & Final Resolution Instructions
Applies To: 220-volt North American Redline CNC VFD Units
Status: Resolved
Issued By: Redline CNC Technical Support
Potentially Affected Order Numbers:
Onefinity Orders 58781 – 63037
(An email will be sent out to potentially affected customers by email)
Overview
After extensive collaboration with our VFD supplier over the past week, Redline CNC
has identified the definitive root cause of the spindle control malfunction affecting a
specific batch of 220-volt VFD units. The issue has been fully diagnosed, and a reliable,
permanent solution is now available.
The affected VFD batch was mistakenly programmed by the manufacturer for 308-volt
3-phase power, which caused the control processor to behave unpredictably when
operated on standard 220–240-volt single-phase shop power. This incorrect
programming directly produced the symptoms described below.
The good news: the fix is 100% programming-based. No hardware replacement is
required.
Symptom Behavior
Affected units exhibited the following behavior:
• Spindle turns on normally.
• Spindle can increase RPM via DRO or g-code.
• Spindle cannot decrease RPM once running.
• Spindle cannot be turned off through normal controls.
• Only powering off the VFD stops the spindle.
These symptoms were caused by the incorrect internal voltage configuration.
Root Cause Summary
Our investigation confirmed:
• The VFD manufacturer shipped a batch programmed for 308-volt 3-phase input.
• When operated on 220–240-volt single-phase power, the processor entered a
fault state.
• This fault caused the spindle control logic to stop responding to RPM-down and
stop commands.
• The issue is programming-related only, not a hardware defect.
The issue was not identified during our standard in-house testing prior to shipment due
to the voltage conditions at our facility. Our warehouse operates on 220V outlets that
typically supply approximately 210 volts, which is below the threshold required to
surface this issue. As a result, the voltage levels during testing were not sufficient to
replicate the conditions where the problem occurs.
To address this, we have invested in a Variac that enables us to simulate higher voltage
conditions—up to 247 volts—during testing. This enhancement has now been
incorporated into our quality assurance process to ensure all units are thoroughly
evaluated under a broader range of operating conditions prior to shipment.
Final Resolution
The corrective action is a simple reprogramming procedure that restores the VFD to
proper operating parameters.
Required Programming Changes
Update the following parameters:
• P8.0.00 = 2468
• P8.0.01 = 3205
After entering these values:
1. Perform a standard factory reset.
2. Reprogram the VFD according to the Spindle Kit User’s Manual Programming
Codes.
Once completed, the VFD will operate normally and safely within a voltage range of
216–264 volts.
Post-Fix Behavior
After applying the updated programming:
• Spindle ON/OFF commands function normally.
• RPM increases and decreases respond correctly.
• Controlled Stop Button (commonly referred to as E-Stop) behavior returns to
normal.
• No further voltage-related lockups occur.
Customer Action Required
If you are experiencing the symptoms described above we have two options for you.
Option 1: Self Programming
• Conduct the final resolution steps provided above.
Quick Start Guide:
RUNAWAY SPINDLE FAULT PROGRAMMING CODES CHEAT SHEET.pdf (33.3 KB)
Watch the step-by-step video:
• If this does not resolve your issue, please contact Redline CNC Support at
Option 2: Customer Support Programming
If you prefer not to perform the programming update yourself, please contact our
Technical Support Team at support@redlinecnc.com and let them know you
would like to send your VFD in for the correction. We will provide a prepaid
shipping label thru email, so you can send the unit to us, and once the update is
completed, we will return it to you at no cost. Please note that the full
turnaround time may take approximately 5–7 days, depending on shipping
transit times.
Support & Communication
Any 220v Spindle Kit purchased after April 26, 2026, has been corrected in production
prior to shipping. We appreciate your patience while we worked closely with the VFD
supplier to identify and resolve this issue. Redline CNC remains committed to
transparency, fast response, and long-term reliability of all spindle systems.
For questions or assistance, please contact: Redline CNC Technical Support
Thank you @Redlinecnc for identifying the underlying issue and providing a solution that can be done by reprogramming.
If anyone needs any assistance, please reach out to us at support@onefinitycnc.com or Redline at support@redlinecnc.com
Thank you!
Kudos to you Redline, I’m relieved the issue and solution are being communicated as well as manufacturing follow up. I’ll be looking at self programming myself.
I just made the programming fix and, from initial testing, it seems to have fixed the issue. Thank you to Redline and Onefinity for the great support and fast response.
well something is not right. I reprogramed the vfd step by step. loaded the test program. homed and probed putting an extra layer of mdf under the probe block so that it would only cut air. I pressed start and the machine moved down to the start position and nothing happened. The spindle did not turn on and the machine never moved at all. I pushed the button on the side of the DRO and yes, the spindle was getting power and turned on. So I tried a different program a flattening program, and again nothing. It moved to the start position and then just sat there. something is wrong. I have had nothing but problems with this unit since I got it. now what? i did the programming thing twice step by step. HELP!!!
solved !!!
Somehow I never got the message that the DRO had to be activated to do the reprogramming. everything is now working as it should. thank you redline for the very prompt and correct solution to a very vexing problem. though I still think an emergency shut off should always work no matter what is happening. Perhaps like they say third times the charm. took me three tries to figure my mistake.
What were the settings before the changes? Mine show both to be zero.
And why do we need to do a factory reset? On most VFDs once you set something, it stays set.
Or is the factory reset on the controller? If so why does it need to be reset?
FWIW, my spindle upgrade order was order number 55787 and has experienced this issue. Just recovering from hand surgery, ( not related to this issue), so will look at programming as time allows. Safe to assume if the incorrect numbers were programmed that they will be visible as I go to make the change, or would you like for me to ship to you for a look?
Contact support@redlinecnc.com and they’ll get you the best answer.