RF & Wireless Systems · Hardware

Wireless Digital I/O Link — 8 Channels

8 relays, 8 inputs — replace the cable with RF.

ELD100 wireless digital I/O link: DIN-rail housing with top terminals, 433 MHz antenna and front status LEDs

Overview

The problem. Carrying a few dry contacts between a pump and a tank, a machine and its control panel, a barrier and a guard booth, or a valve and a control room normally means pulling cable: trenching, conduit, road or stream crossings, third-party land, and the risk of lightning and breaks. In most applications the information is just 1–8 bits (full/empty, run/stop, open/closed, fault), yet cable costs and permits inflate the project. GSM/IoT solutions add subscriptions, cloud dependency and latency, which is overkill for a simple level control.

The solution. The Wireless Digital I/O Link carries digital signals over RF between two (or more) endpoints. A contact change at the input end immediately switches the relay at the far end; periodic status refreshes keep the link continuously verified. If communication is lost, the relays drop to a defined safe state (for example, the pump stops). To a PLC, the link looks like an I/O card shared by both panels: input terminals on one side, relay contacts on the other.

Generations. The ELD100 generation in the field delivers kilometer-class range with LoRa. The new series is planned to offer the same function on DIN rail with the EM-G0L-433 module and the EC-DIO8 carrier board, in 433 MHz and optional 868 MHz versions.

433 MHz wireless link between two ELD100 units mounted on DIN rails in two electrical panels — In use

Features

Defined safe state: open / close / hold selectable per relay on link loss; optional “link fault” relay.
Float / contact filter: an adjustable delay that prevents false triggering from fluctuating level floats; proven in the field on the ELD100 generation.
Periodic refresh + event transmission: low airtime, high reliability.
Production tooling: ID/channel programming and automated testing at production.
TargetRole selected by firmware: the same board works as a transmitter, receiver, bidirectional endpoint or repeater.
TargetService tool and fixture: field pairing and testing with the Module Programming/Test Fixture + SDK Package.
TargetSecurity and maintenance: AES encryption, network ID (NetID), OTA updates, RSSI reporting and LED indication.
TargetModbus RTU slave: link status and I/O states readable by a PLC.
TargetBattery transmitter and 868 MHz options: a battery-powered transmitter for contact monitoring only; an 868 MHz version.
TargetMixed systems and counter mode: runs on the same network as the analog sister board (Wireless Analog & Digital Data Link, EC-AIO); an input counter mode for pulse counting (Wireless Meter Reading Node).

Variants

Variants
Model code	Role	Inputs	Outputs	Supply	Status	Request a quote
ELD100 (MODM0-ELD100)	Bidirectional / receiver	8 digital inputs	8 relays	12–24 VDC	In the field	Request a quote: ELD100 (MODM0-ELD100)
DIO8-TXTarget	Transmitter (input end)	8 opto-isolated inputs	— (status LED)	9–36 VDC	Planned	Request a quote: DIO8-TX
DIO8-RXTarget	Receiver (output end)	—	8 relays, 5 A	9–36 VDC	Planned	Request a quote: DIO8-RX
DIO8-BITarget	Bidirectional	8 opto-isolated inputs	8 relays	9–36 VDC	Planned	Request a quote: DIO8-BI
DIO8-TX-LPTarget	Battery transmitter (contact monitoring)	8 inputs (wake-up)	—	Battery	Planned	Request a quote: DIO8-TX-LP
DIO8-REPTarget	Repeater (same hardware, firmware profile)	—	—	9–36 VDC	Planned	Request a quote: DIO8-REP
DIO16 (EC-DIO16)Target	Extended variant	16 digital inputs	8 relays	9–36 VDC	Planned	Request a quote: DIO16 (EC-DIO16)

Specifications

Values marked “Target” are design targets, next-generation values or chip-vendor data; they are updated as measurement and certification are completed.

Current system (ELD100)
Generation	ELD100 (N2), in the field
Frequency	433 MHz ISM band, LoRa (SX1268)
Inputs / outputs	8 digital inputs, 8 relay outputs
Supply	12–24 VDC
Pairing	ID and channel programmed at production

Radio (new series)
Frequency band	433.05–434.79 MHz, 8 channels; 868 MHz as an optionTarget
Output power	+22 dBmTarget
Receiver sensitivity	−129 dBm @ SF11/BW125 (chip datasheet)Target
Modulation	LoRa SF7–SF12; packets < 20 bytesTarget
Antenna connector	On-board female SMA, 50 ΩTarget

Range
Open field	≥ 2000 m (SF9, 2 dBi omni antenna, 2 m height)Target
Industrial / indoor	≥ 300 mTarget

Communication & security
Encryption and addressing	AES-128-CCM; network ID (NetID) + 16-bit address; replay counterTarget
Field pairing	With a service toolTarget
Systems on the same site	≥ 8 (channel × network ID)Target

Performance & fail-safe
Command latency	< 100 ms @ SF7; < 500 ms @ SF10Target
Fail-safe on link loss	Adjustable 5–300 s timeoutTarget
Watchdog	Independent hardware watchdog (IWDG)Target

Power
Supply	9–36 VDC; reverse-polarity and TVS protectionTarget
Consumption	Standby ~30 mA @ 12 V; all 8 relays energized +~560 mA @ 12 V (~70 mA per relay); transmit peak +120 mA @ 3.3 VTarget
Battery transmitter (TX-LP)	2 × AA / Li-SOCl2; sleep < 10 µA; battery life depends on the number of transmissionsTarget

Inputs / outputs
Digital inputs	8 × opto-isolated; 12–24 V or dry contact (with internal 12 V supply); 3 mA; 10 ms filter + adjustable float filterTarget
Relay outputs	8 × relay NO/NC, 5 A / 250 VAC, varistor-protectedTarget
Service interface	UART / SWD
Field communication	RS485 (with the EC-485 board); Modbus RTU slave for I/O read-out by a PLCTarget
Indicators	Power, link, TX/RX, 8 × input and 8 × relay LEDsTarget

Mechanical & environmental
Housing	35 mm DIN rail, 6 modules (~108 mm)Target
Ingress protection	IP20 (in-panel); IP65 enclosure option for outdoor useTarget
Operating / storage temperature	−25…+70 °C / −40…+85 °CTarget
Humidity	5–95 %, non-condensingTarget

Warranty & service
Warranty	2 yearsTarget
Spare-parts support	5 yearsTarget
Manufacturing and service	Ankara

Applications

Well pump and tank level
Booster stations and chlorination
Machine start/stop and fault signals
Door and barrier control
Irrigation valve on/off
Alarm and warning collection
OEM wireless I/O expansion

Water: between a well pump and a tank level float (Wireless Well-Tank Control System); booster stations; chlorination.
Machinery: start/stop, fault and ready signals; sandblasting, pumps, compressors (Wireless Machine Start & Control).
Doors / barriers: barrier relay driven from a remote button or card reader; door contact feedback (Smart Door Control & Access).
Irrigation: valve on/off with feedback (Wireless Irrigation Control System).
Alarms / warnings: sirens, beacons, dry-contact alarm collection; fire contacts (Wireless Fire Alarm System (Firesens)).
OEM: wireless I/O expansion for machine builders (Elmes OEM Device Control Platform).

Compliance & documentation

There is no product-level CE declaration of conformity or test report yet. Documentation is prepared in stages, starting at module level; as the first carrier board of the series, EC-DIO8 has priority.

CE – RED 2014/53/EU (EN 300 220-2, EN 301 489-1/-3)
Starting at module level
Target
EMC — EN 61000-6-2 / EN 61000-6-4
Target
LVD — EN 61010-1 or EN 62368-1 (250 VAC relay outputs)
Target
RoHS declaration
Target
CE declaration of conformity, datasheet, terminal diagram and user manual
Target

References

Some of the organizations using this product family.

İSKİ
Şeker Fabrikaları A.Ş.
Sançim Bilecik Çimento
Rize Pazar Belediyesi
Atom Enerji Kurumu (TAEK)
Gemi Kaya Holding

Frequently asked questions

Is a PLC required?

No. The link behaves like a cable between two panels; contacts are wired directly. If there is a PLC, the link connects to its inputs and outputs; read-out over Modbus RTU is planned.

What happens to the relays if communication is lost?

After the configured timeout, each relay goes to its defined safe state (for example, the pump stops); the link LED and the link-fault relay signal the condition.

How many links can run on the same site?

At least 8 independent links through channel × network-ID combinations; a star topology with up to 16 endpoints per hub is planned.

What is the range, and how can it be extended?

With LoRa, kilometer-class range in open field is the target; it can be extended with an outdoor antenna, more height, a directional antenna (Industrial RF Antenna Series) and a repeater endpoint.

Does it work with my existing well-tank system?

Protocol compatibility with the ELD100 generation is planned through a migration firmware. It does not talk directly to first-generation (N1) well-tank systems; it runs alongside them as a separate link.

Can the inputs run on batteries?

Yes, with the planned battery transmitter option (DIO8-TX-LP): contact monitoring only, with wake-up operation. The battery version has no relay outputs.

Does it carry analog signals (4–20 mA)?

This product is digital. For analog signals, the Wireless Analog & Digital Data Link and the EC-AIO sister board run on the same network.

What about warranty and service?

A 2-year warranty is planned; service is in Ankara. Over-the-air (OTA) firmware updates are also on the roadmap.

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