What the head station carries
- It is the head of a distributed I/O rack, running EtherNet/IP, PROFINET, and Modbus TCP, and it keeps the slave map.
- Modules can be swapped hot, a fault is reported per channel, and a redundant ring heals quickly.
- Surge protection and zoned ground are sized for a cabinet. Digital, analog, and temperature modules plug on.
- On a large plant the I/O sits in zones, so the copper runs are shorter and EMC is easier.
Signals stay near the machine
Field signals are collected next to the machine and sent over industrial Ethernet to a PLC or a DCS. That is the I/O node used on discrete lines, logistics, and utility cabinets.
SimtoLink supplies the GSD and EDS files, a wiring table, and an RSTP ring template. Volume jobs can ship with channel labels and made-up cables, so less work is left inside the cabinet.
How the coupler stays up
IEC 61000-4 level 4 items are on the record. Ports have surge and reverse-polarity protection. Ground is zoned so a loop or common-mode noise is less likely to drop a slave. Outdoor and coastal orders can take a higher ingress rating and a corrosion coating.
Parameters and thresholds load as a batch. Selected models store an event or a waveform. OTA carries settings and firmware. Accept the coupler with a power-on self-test, a time sync, and a sample of channels. For metering or safety, SimtoLink helps with a third-party metrology submission and the type-test file.
Hardware figures
Typical order, for selection and for a bid clause. For a wider range, a redundant supply, or an intrinsically safe explosion-proof variant, ask SimtoLink for the hardware specification and the installation guide. Order codes can differ slightly; the nameplate and the papers in the box decide.
| Item | Specification | Note |
|---|---|---|
| I/O | 1024 points | Distributed expansion |
| Scan cycle | 2.3 ms | Instruction-level |
| Programming | CODESYS | Online debug |
| Communication | Modbus TCP | Dual port |
| Redundancy | CPU hot standby | Bumpless switchover |
| Safety | Standard | TÜV |
| Storage | Program 8 MB | Holds through a power loss |
| Operating temperature | -16～57 ℃ | Wide temperature range |
| Supply | AC 220V | Surge 4kV |
| Certification | CE | Industry compliance |
Where the head station sits
Three lines where the coupler is usually proved before the slaves are left on it.
Automotive and discrete assembly
I/O at the station, fed from a conductor bar or a drag chain, so a long multi-core run and its failure points are not pulled.
Water and pump stations
Valves, level, and pump status come in by zone. Outdoor cabinets ride a ring up to the control room.
Sortation and conveyors
Photoeyes, barcode readers, and drive DI/DO pack in densely, and a millisecond refresh keeps the sort cycle.
Install, ground, and recheck
- Confirm the supply window and polarity before the coupler is powered. Measure the bus and the breaker if the feed is uncertain.
- Shielded twisted pair, shield at one end, kept off long power-cable runs.
- In the lab, read and write both ways and trip one threshold against the PLC, then move the coupler to the line.
- Outdoors, let water leave and air move, look at the seal, and keep the lightning earth inside the local rule.
- Every 24 months, sample a set of channels and archive the log.
Order, documents, and support
SimtoLink supplies the hardware specification, the outline, a wiring table, and a sample project. Volume orders can include a sample review and a factory inspection. Warranty and calibration follow the contract and the papers in the box.
Related I/O and protocol hardware
Distributed I/O and the converters that sit next to it: