The Micro800 family, Micro810, 820, 830, 850, 870, is Allen-Bradley’s small-controller line. A conveyor section, a single machine, a standalone pump skid: the scale of job a full CompactLogix would be overkill for. It’s programmed in Connected Components Workbench rather than Studio 5000, and it reads over the same EtherNet/IP wire as its bigger siblings: symbolic tag names, no separate SDK. If you’ve read the CompactLogix/ControlLogix guide, the tag addressing here will look familiar. What’s different is smaller than you’d expect.
None of that difference shows up as extra work on your end. If anything it’s less. A Micro800 job tends to be a faster setup than a comparable Logix one, since there’s less to configure and less to ask a program’s history about.
Before you start You’ll need the controller’s IP address, Connected Components Workbench (or a tag list from whoever wrote the program) to confirm exact tag names, an Ethernet drop, a fixed IP, and the Spall gateway on the same network. Spall reads only. It never writes to the controller.
1. Symbolic tags, the same idea as Logix, simpler underneath
A Micro800 program names its data the same way a Logix5000 program does, MyTag, Motor1_Speed, PartCount, real words instead of bare numeric addresses. There’s no PLC-5 or SLC-500 legacy addressing scheme hiding underneath a Micro800 the way there sometimes is on an older Logix migration. Every Micro800 program uses symbolic tags, so the “which situation am I in” question that drives cost on a Logix job doesn’t apply here. Open the project in Connected Components Workbench, or ask whoever wrote the program for a tag list, and write down the exact names. Tag names are case sensitive.
Addressing supports the same shapes you’d expect: a plain tag (MyTag), an array element (Motor1[3]), a dotted member path into a structured tag (Line1.Status), and a specific bit within a word or dword tag using a slash suffix (MyWord/5 for bit 5). All of that reads directly, no extra mapping step.
2. What differs from a CompactLogix
Two real differences, both in your favor for a small controller. First, there’s no backplane slot to configure. A CompactLogix connection routes through a slot number in its rack. Micro800 controllers are standalone units with no backplane to speak of, so that field doesn’t exist here, one less thing to get wrong. Second, there’s no bare-numeric-tag detour. A Logix program migrated forward from an older PLC-5 or SLC-500 project can still carry unnamed addresses that need mapping before they mean anything, the single biggest cost variable on that guide. Every Micro800 program is symbolic tags from the start, so that whole question doesn’t come up.
What’s the same: the wire, the port, and the read-only posture. A Micro800 speaks EtherNet/IP exactly the way a Logix controller does, just without the extra addressing baggage a bigger, longer-lived controller family can carry.
One practical consequence for scoping a job: a small controller usually means a small program, and a small program usually means fewer tags worth mapping in the first place. Where a CompactLogix on a complex line might carry dozens of values worth reading, a Micro800 running a single machine or a standalone skid often has five or six that matter: run status, a fault or alarm bit, maybe a part count if the program keeps one, and a couple of process values. Confirm which of those the program maintains before assuming a value exists just because a similar machine elsewhere has it. A Micro810 keeping minimal state is common, and checking the tag list instead of guessing from a bigger sibling’s setup is the safer default.
3. Confirm the controller answers
EtherNet/IP listens on the standard port 44818. From a PC on the same network:
nc -vz 10.0.6.15 44818
-> Connection to 10.0.6.15 44818 succeeded!A refused connection here usually means a firewall or VLAN boundary between the machine network and the gateway, or the controller’s Ethernet port is on a different subnet, not a Spall problem. This test doesn’t touch Spall yet.
4. Add the source in Spall
In Spall, add the machine, choose Allen-Bradley Micro800 as the source, and enter the controller’s address:
10.0.6.15There’s no slot or routing path to set. The connection is just the address. Assign the Spall gateway and save.
5. Add a tag per value
For every point you want, add a tag with its exact symbolic name from step 1. An array index, member path, or bit suffix is entered the same way it reads in the project. If the same physical value is also available as a continuous reading and a state flag, pick whichever one you need first. Both can be added as separate tags later.
Once the first tag saves, run the machine through a real cycle and watch the value move in Spall before wiring in the rest. A tag that reads a fixed number that never changes usually means the wrong array index or member path, not a dead connection, since the read itself still succeeds. Catching that on tag one, while there’s only one value to check, is faster than tracing it back after five more tags are already added on top of the same mistake.
What Spall does with this data
Availability. A tag mapped to run status splits every hour into running, idle, and down.
Downtime and reasons. Each stop is caught the instant the mapped signal changes. Operators tag the reason, ranked into a Pareto the same way as every other connection method.
Production. A tag mapped to a part count drives target-vs-actual by shift and job.
Quality and OEE. Availability, performance, and quality still roll into one OEE view, dollar-ranked, whatever’s feeding it.
One thing worth repeating Spall issues EtherNet/IP read requests only. It never writes a tag back to the controller, not a setpoint, not a reset bit, nothing. Worst case if it can’t reach the controller is a gap in the chart. The line keeps running exactly as it would with no gateway attached at all.
Quick recap
- Micro800 controllers (810 through 870) use symbolic tag names from the start, no bare-numeric legacy addressing to sort through
- Tag addressing supports plain names, array elements, dotted member paths, and a bit suffix for a specific bit of a word
- No backplane slot to configure, unlike a CompactLogix. The connection is just the IP address
- Port 44818 is the standard EtherNet/IP port. Confirm it answers before touching Spall’s side
- Add the controller’s address, then a tag per exact symbolic name, case sensitive
- Every new tag lands in the Signal inbox unclassified until someone tells Spall what it means
If a tag list is hard to pull from the running project, bring a screenshot of Connected Components Workbench’s tag browser to a pilot call. We’ll help sort out what’s worth mapping first.