When working in wireline perforating and setting operations, the most dangerous mistakes often come from the smallest oversights. One day, a simple power control misstep led to an unexpected detonation—and it nearly caused a serious incident.

The Setup: Routine Gamma Gun and Setting Tool Run

We were on-site for a plug setting job, using a Gamma Gun with a setting tool to place a bridge plug at a precise depth. The crew had worked this setup many times before, and everything seemed normal.

The steps were standard:

• The wireline truck was positioned, and the toolstring was rigged up.
• The Gamma Gun was run into the well to a safe depth.
• The Power Control Box was opened, and Enable was selected.

Then, something went very wrong.

The Unexpected Detonation

Within seconds of enabling power, the plug prematurely fired out of zone.

At first, the team thought there might have been a malfunction in the tool or the control panel. After immediate troubleshooting, we checked:

• The interface panel and tool integrity—both tested fine.
• Voltage readings on the Power Control Box—unexpected spikes were present.
• The polarity switch and power knob positions—this is where the problem was found.

What Went Wrong?

The cause of the misfire was identified as a power control setup error:

• Voltage control knobs were left turned up.
• Polarity switch was not in the neutral position.
• The panel power switch had been left ON.
• When Enable was selected, power was instantly applied to the detonator.

The oversight in power control settings led to an unintended detonation the moment Enable was activated.

Fixing the Issue: Best Practices for Power Control Safety

To ensure this never happened again, we implemented strict power control procedures:

• Always return voltage control knobs to 0 when shutting down tools.
• Ensure the power switch is OFF when not in use.
• Keep the polarity switch in the neutral position before enabling power.

Additionally, a long-term solution was introduced:

• A new Warrior PSXD Rev 7 interface card was installed in control panels.
• This modification prevents the power control from enabling if voltage knobs are left turned up.

As updated panels became available, they were distributed to districts to replace older models.

Key Takeaways for Wireline Engineers

• Power control safety is critical.
  • Even minor setup mistakes can result in unintended detonations.
• Always verify control panel settings before enabling power.
  • Double-check voltage knobs, polarity switches, and power states.
• Use updated control panels with built-in safety measures.
  • The Warrior PSXD Rev 7 card prevents accidental detonation errors.
• Strict shutdown procedures must be followed.
  • When finishing a job, always reset power settings to a safe state.

Final Thoughts: A Small Oversight Can Lead to a Big Problem

In wireline services and perforating operations, power control safety is not optional—it’s critical. That day, a simple power knob left in the wrong position could have caused an even bigger problem.