What 6,000 Microamps Taught Me About Correlation and Confidence in Cased Hole Logging

Posted on by Crissa Fel Tawadan

In this line of work, you get used to trusting the numbers—volts, amps, counts, depths. But every now and then, the numbers throw you off. That’s what happened the first time we ran a Titan CCL alongside a Dyna firing system on a cased hole wireline job. It wasn’t a misfire. It wasn’t a failure. It was a successful run with an unexpected twist—one that pushed us to rethink how we approach coil resistance, current signatures, and correlation in wireline logging.

Let me walk you through it, because the lesson we pulled from that run is now built into our wireline courses, our gunstring prep, and every troubleshooting sheet we build for the Dyna system.

The Setup: A Routine Pump Down Job with a New Twist

This was a pretty standard horizontal wireline setup—pump down perforating, multi-stage perforation well, tight cluster spacing, and fast cycle times. We were using a DynaSelect firing system with built-in logging and shooting sequences, and we’d swapped in a Titan casing collar locator (CCL) for the first time.

Everything else was textbook: the wireline truck rigged up, the wireline tools in order, the logging cable clean and tested. What stood out was during the pre-job switch test.

Instead of the typical ~16,000 microamp draw we were used to seeing from our older CCLs, we got a spike just over 22,000 µA. That six-thousand-point difference stopped the whole crew cold.

Is It Firing? Or Is It Failing?

Every field engineer knows that weird current readings trigger immediate concern. A jump like that, especially on a delicate firing head circuit, raises all kinds of red flags.

  • Did we wire the head incorrectly?

  • Is the igniter shorting?

  • Are the gun parameters set wrong in the software?

We pulled the dumpfile, compared the readout against the known values, and realized the truth: this wasn’t a fault. It was a feature.

Titan’s CCLs simply draw more current due to their coil design. The reading was valid—it was just different. And that difference, if not understood, could easily lead to misdiagnosing a misfire or halting a good run.

Why This Matters for Wireline Engineers and Providers

In the cased hole logging service market, consistency is key—but you can’t let routine blind you to design evolution. Wireline technologies evolve. Downhole tools get smarter. And if your crews aren’t trained on the differences, they’ll interpret “new normal” as “something’s wrong.”

The biggest lesson? You must track and document CCL resistance values, especially when mixing tools from different manufacturers.

The Fix: New SOP for Titan CCLs and Dyna Systems

We updated our procedure for running Titan CCLs with DynaSelect to include a few critical steps, all aimed at eliminating confusion and ensuring seamless operation.

CCL Integration SOP for Dyna Gun Systems

1. Log CCL Resistance Before Deployment

  • Use a precision meter to record the CCL’s coil resistance.

  • Enter the resistance value into the gun parameters window of the Dyna software.

  • This allows accurate simulation of expected current readings.

2. Flag Higher Initial Currents in Job Sheets

  • Any Titan CCLs expected to draw ~22,000 µA should be noted on the run sheet.

  • This preempts confusion during live dumps and troubleshooting.

3. Standardize Dumpfile Interpretation

  • Train crews to distinguish between legitimate high-draw CCLs and true short conditions.

  • Include example current logs in crew SOP binders.

4. Avoid Mixing CCL Types Without Resistance Notes

  • When using both Titan and other CCLs in the same operation, clearly label and log their resistances separately.

5. Run Simulations with Expected Parameters

  • Run full power-up simulations in the shop using the real CCLs and actual toolstring hardware before heading to the field.

Why This Practice Supports Complete Wireline Solutions

In today’s wireline services oil and gas world, especially in high-efficiency frac environments, your systems are only as reliable as your data. When it comes to wireline perforating, misinterpreting electrical data can lead to:

  • Missed perforation zones

  • Unnecessary fishing wire line operations

  • Delayed well perforation

  • Increased NPT in the field

  • Client frustration over seemingly “invisible” tool issues

By proactively logging CCL resistance, we’ve improved:

  • Firing sequence reliability

  • Correlation confidence for formation evaluation

  • Depth accuracy for cement bond log (CBL log) and production logging services

Building This Into Wireline Courses

This topic is now a core module in our wireline tech and gun prep training programs. We teach engineers how to:

  • Use multi-meters to verify coil resistance

  • Adjust Dyna gun parameters with accurate values

  • Read dumpfiles with an understanding of tool-specific signatures

  • Use Titan vs. legacy CCLs across different cased hole wireline toolstrings

They also learn the importance of clear communication across shift handovers, especially when tool swapping is involved.

Trusted Wireline Control Starts at the Coil

At the end of the day, it doesn’t matter how advanced your wireline control systems are if your team doesn’t know what “normal” looks like. Titan’s CCLs work flawlessly—but only if you know how to read them.

In wireline logging, control isn’t just about cables and software. It’s about foresight. If your crew sees a current spike and doesn’t panic, you’ve done your job as a leader. You’ve built a team that understands both the tools and the tech.

Final Thoughts – Know Your Numbers, Trust Your Gear

This experience reminded us that not all changes are problems—some are upgrades. But if we don’t train on them, we miss the benefit and create confusion.

So if you’re running a wireline company, managing crews, or training your next round of engineers, start logging resistance values. Start annotating your job sheets. And start seeing high current not as a threat—but as a signature of performance.