Lookup/Your meter/Electric
Electric meters — the best payload, or nothing at all
No middle ground here. An electric meter either hands you interval history no other meter type carries, or it hands you nothing. The faceplate tells you which.
Electric is the most polarised of the three utilities. The reason is on the overview page: an electric meter is the only one with unlimited power, so its designers were free to build a two-way encrypted mesh network instead of a simple broadcast. Plenty of them did.
Read the faceplate first
A spinning metal disk behind glass → no. Definitively, permanently no.
This is an induction-disk meter, and it is a purely mechanical instrument: the aluminium disk is driven directly by eddy currents induced by the current it is measuring, and a gear train counts its turns. There are no electronics inside. No firmware, no transmitter, no frequency, nothing to find at any price.
This single check disqualifies more setups than everything else on this site combined. If you take one thing away: go look at your electric meter before you buy anything.
A digital LCD readout → maybe, and worth the effort to find out
Digital does not imply ERT. It might speak IDM, which is the best thing on the band, or it might be a closed mesh node. Look up the FCC ID — the upside is large enough to justify the ten minutes.
Digital, and your utility calls it a "mesh" network → probably not
Mesh meters relay packets through each other to a neighbourhood collector rather than broadcasting a simple bubble-up reading. The formats are proprietary and commonly encrypted. You may well see energy in the band and never decode a byte of it.
If it does speak IDM
IDM is the most informative message on the band by a wide margin, and it is worth understanding why before you dismiss electric as a hard case.
| Property | Typical |
|---|---|
| Band | 902–928 MHz |
| Message | IDM, sometimes SCM / SCM+ |
| Payload | 47 differential intervals at 5 minutes each |
| History depth | ≈ 4 hours per packet |
| Encryption | None on IDM |
Every other message type on this band is an odometer reading — a single cumulative total, from which you derive consumption by subtracting. IDM instead carries differential consumption across 47 recent five-minute buckets, which means a single successfully decoded packet hands you roughly four hours of five-minute-resolution history.
Because each packet is self-contained history, a missed packet is not a gap in your data. Any one decode in the next four hours backfills what you missed. That is a completely different reliability posture from SCM, where losing a packet means losing that sample forever.
Five-minute resolution is also enough to actually see appliances — a well pump cycling, an oven's duty cycle, an EV starting to charge. Cumulative gas readings never give you that.
If it does not, use a CT clamp instead
This is the honest recommendation, and it is worth stating plainly because the alternative is better than what you were trying to do anyway.
A clamp-on current transformer at your service panel measures current directly by induction. Nothing has to be wired into the live conductors, no utility equipment is touched, and no protocol has to be reverse-engineered. Fifty dollars of hardware gets you second-by-second resolution on individual circuits.
That is not a consolation prize. It is strictly better data than any meter broadcast, including IDM:
| Meter broadcast | CT clamp at the panel | |
|---|---|---|
| Resolution | 5 min at best | Sub-second |
| Per-circuit detail | Whole house only | Per circuit |
| Depends on the utility? | Entirely | No |
| Survives a meter swap? | No | Yes |
| Needs an electrician? | No | Panel access; often yes |
The one thing the meter broadcast has that a CT clamp does not is agreement with your bill — it is the utility's own number, which makes it the right instrument for auditing a charge you dispute. For everything else, the clamp wins.
Receiving an unencrypted broadcast is passive and involves no contact with utility equipment. Opening, unsealing, or interfering with an electric meter is a different matter entirely — it is the utility's property, the seal is there for revenue-protection reasons, and breaking it is a serious matter regardless of intent. Work at your panel, on your side of the meter, or not at all.
Next
Where this leads.