It is not a PLC and does not replace one
There is no ladder logic, no deterministic scan time and no safety rating. Where an interlock has to hold in milliseconds with no network, that is a PLC and it should stay a PLC. Sphynx watches and reports.
Sphynx
The field unit that does the measuring. Four analog inputs, a run status and a pulse totalizer, read about once a second, timestamped at the device and published over LTE.
The full specification is below, including a section on what it cannot do. That section is there because it is the one that saves everybody time: if you need a safety rated interlock or Modbus polling today, you should find that out on this page rather than three calls in.
Specification
The unit is pre-production. Figures marked To be confirmed are design targets rather than measured results, and items marked Planned are not in the current firmware. Everything unmarked is verified against the device as it runs today. Ask for any figure that matters to you and you will get the real answer rather than the brochure one.
Measurement
- Analog inputs
- 4 × 4-20mA, isolatedEach input is read independently, and an absent or failed input reports as no value rather than as zero.
- Analog resolution
- 12 bit
- Analog accuracy
- ±0.5% of full scaleTo be confirmed
- Digital inputs
- 2, dry contactOne run status, one pulse input for the totalizer. Both active low.
- Totalizer
- Configurable increment per pulseThe increment is set remotely and takes effect without a site visit. Resets daily at 08:00 local, and the reset is published so a missed one is visible.
- Sample interval
- About 1 secondEvery input on every pass. Publishing can be slower than sampling, so a fast local alarm does not mean a large cellular bill.
Connectivity
- Cellular
- LTE Cat-4, global bandsSIM7600G. Falls back to 3G where LTE is unavailable, which still matters in parts of Alberta and Saskatchewan.
- Local access point
- WiFi, on deviceFor on site diagnostics and for cameras. Up to four clients, and it does not route to the internet.
- Local status endpoint
- HTTP, on the access pointHealth and connection state readable from a phone standing at the panel, with no cellular signal needed.
- Wired ethernet
- Planned
- Satellite
- Planned, via the wired pathThe intent is that a satellite terminal presents as ethernet, so the device needs no satellite specific firmware.
Power and environment
- Supply
- 9 to 30 VDCTo be confirmed
- Typical consumption
- Under 3 WTo be confirmed
- Operating temperature
- -20 to +60 °CTo be confirmedThe limiting component is the display rather than the processor, so a version without a display would extend the low end.
- Enclosure
- IP65, NEMA 4XTo be confirmed
- Mounting
- DIN rail or panelTo be confirmed
Data and alarms
- Store and forward
- 30 days at 1 minute resolutionTo be confirmedBuffered on the device through a backhaul outage and delivered in order when the link returns, so an outage is a delay rather than a hole.
- Edge alarm evaluation
- PlannedThresholds evaluated on the device so an alarm fires while the backhaul is down. Not in the current firmware.
- Transport
- MQTTOne topic per value, so a third party system can subscribe to exactly what it needs.
Security
- Per device credential
- Planned
- Encrypted transport
- Planned
- Secure boot
- Planned
- Flash encryption
- Planned
- Signed firmware with rollback
- PlannedA failed update must return the device to the previous working firmware without a site visit.
What it cannot do
Every one of these is a real limitation rather than a soft sell. If one of them rules us out, it rules us out now instead of after you have bought something.
No 0-10V or thermocouple inputs
Four 4-20mA loops and two dry contacts. A different signal needs a transmitter in front of it.
No Modbus polling of other devices yet
It reads its own inputs. Pulling registers out of an existing flow computer or VFD is a common request and it is not built.
It needs cellular coverage or a wire
The local access point works with no signal at all, so a site visit is never blind, but nothing reaches the cloud until there is a path. Satellite is planned rather than shipping.
The current firmware is a bench proof
It reads inputs and publishes them reliably. The security and store-and-forward items above are marked planned because they are planned, not because we are being modest.
Put one on something you own
A unit on real equipment for a couple of weeks answers more than any specification table can, and it is the only way to find out what your own cellular coverage is actually like.