LScope
Troubleshoot a stopped machine from your phone.
Read live tags, compare signals on one time axis, and share a diagnostic report before you leave the floor. LScope does not write tag values.
Read-only by designWhat it does
Watch the tags that matter
Browse the controller's tags, group them by subsystem, and label them the way you talk about them — "Measured Force, lb" rather than Scale_LBS. The controller's own name stays underneath for when you open the program.
See what happened in what order
Compare up to eight tags on one shared time axis, in separate lanes so signals with different units stay readable. Freeze the chart and drag a cursor across it to read every lane at the same instant.
Catch an intermittent fault
Set an alarm on any tag and it latches — a fault that trips and clears while you are looking the other way still leaves evidence. Alarms run while the app is open and on screen; LScope does not monitor in the background.
Leave with proof, not a memory
One tap captures a diagnostic snapshot — every watched tag, its value, latency, controller identity, alarm state and your own note. Trends export as a PNG for a text message, a CSV for a spreadsheet, or a one-page PDF that goes straight into a work order.
It tells you when it does not know
Readings that stop arriving are marked stale instead of sitting there looking live, connection health is reported in plain language, and the app names the interface it is actually using — not the one the phone would prefer.
Measured
The 29 ms figure is five tags read in a single round trip against one CompactLogix 1769-L24ER-QB1B over a wired link — 3.0× faster than reading them one at a time. One controller, five tags, one network. Yours will differ.
Compatibility
- Device
- iPhone and iPad, iOS 17.6 or later
- Controllers
- Allen-Bradley Logix over EtherNet/IPCompactLogix and ControlLogix processors, addressed by IP and backplane slot.
- Verified on
- CompactLogix 1769-L24ER-QB1BA core aim of the beta is to run LScope against as many controllers as testers can put it in front of, and grow this list. It speaks standard Logix data access, so other CompactLogix and ControlLogix processors should work.
- Data types
- BOOL, SINT, INT, DINT, LINT, REALPlus bit access within a word. User-defined types, arrays and strings are not read yet.
- Tag scope
- Controller-scoped and program-scoped tags
Getting on the network
Three routes onto a controls network. All three are tested.
Ethernet adapter
The most reliable route, and the one to reach for when Wi-Fi at the machine is marginal. Plug an adapter into the phone and land directly on the machine subnet.
Wi-Fi
Join the plant or machine wireless network. Convenient, and only as good as the coverage where the machine actually is — often the worst spot in the building.
VPN
If your controls network is reachable over a VPN, connect it and LScope reaches the controller through it like any other route — useful for a machine you are not standing next to.
Tested adapters
The two adapters actually used to read a controller from a phone. A cheap adapter that enumerates as the wrong device class is a bad thing to discover at a stopped machine.
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Anker PowerExpand USB-C to Gigabit Ethernet
iPhone 15 and later, and recent iPads
MFi-certified Lightning to Ethernet, with charging port
iPhone 14 and earlier · 100 Mbps, passes power through
What else you need
- The controller's IP address.
- Its backplane slot. A CompactLogix with a built-in Ethernet port is slot 0; a ControlLogix chassis routes through the Ethernet module to whatever slot the processor sits in. Getting this wrong is the most common reason a connection registers but every tag read fails.
- Permission to be on that network. Many plants treat the control network as restricted, and connecting a personal device can be a disciplinary matter regardless of the fact that LScope cannot write anything.
Read-only
LScope has no write service in it — not a setting that is switched off, but code that was never written.
That is what gives a plant manager or an IT department a reason to allow it on the control network at all.
Safety
LScope is a diagnostic instrument, not a safety device, and not part of any machine's safety system. Never use it to decide a machine is safe to approach — follow your lockout/tagout procedure. A reading can be stale, wrong, or from the wrong controller.
Beta
The private beta is opening now.
LScope is looking for a small group of controls engineers and maintenance technicians to use it on their own machines. If you look after Logix equipment and would reach for this next time something stopped, get in touch.
Testing runs through TestFlight. Builds expire, things will change, and what testers report shapes what gets built next — starting with pre-trigger event capture, which records the thirty seconds either side of a fault and is the feature this is really being built for.