Y503-2220-L LoRaWAN RTU User Manual

Y503-2220-L Specification

Configuration: 2 DI + 2 switched voltage DO + 1 voltage input (AV) + 1 current input (AI); isolated RS485; no AO.

Contents

1. Scope and Preparation
2. Installation and Power
3. Field Wiring
4. Local Configuration
5. LoRaWAN Commissioning
6. Signal and Control Verification
7. Application Integration and Handover
8. Maintenance and Troubleshooting

1. Scope and Preparation

Y503-2220-L acquires field signals and RS485 data, then sends them through a LoRaWAN gateway to a local or remote Network Server and application. Downlinks can control its two voltage outputs and supported serial or configuration functions.

The two analog inputs have fixed roles: AV measures 0–10 V and AI measures 4–20 mA. Use the terminal names AV and AI in wiring and application records to avoid confusing them with two selectable analog channels.

Prepare the RTU, antenna, suitable DC supply, field wiring, and a gateway with matching radio settings. Obtain these delivery items before commissioning:

Item	Required information
Device configuration	Hardware revision, firmware version, and matching PC tool or service procedure
Radio settings	Regional plan, channel group, AS923 sub-plan if applicable, and Class A/C profile
Activation	DevEUI and OTAA credentials, or ABP address and session keys
Field integration	DI type, output load, analog sensor wiring, and RS485 settings
Application protocol	Uplink fields, FPorts, encoding, scaling, downlink commands, and responses
Output behavior	Startup state, pulse/timer behavior if used, and behavior after loss of communication

Keep device keys and passwords in the project's credential store. The configuration screens and command bytes depend on the supplied firmware; use the matching delivery guide.

2. Installation and Power

1. Check the enclosure, antenna, terminals, and supply for damage.
2. Mount the 104 × 97.6 × 25.6 mm enclosure using the supplied drawing and hardware. Keep it dry, ventilated, and accessible.
3. Connect PE to the installation earth as specified by the site wiring design.
4. Connect the LoRa antenna before applying power. Place it clear of metal enclosures and interference sources.
5. With power off, connect one regulated DC 9–28 V supply, observing polarity. The DC jack and +/− terminals are connected internally; do not connect independent supplies to both.
6. Check all field wiring, then apply power. POWER should be steady and RUN should blink after startup.

The reference adapter is DC 12 V / 1 A. Use a 2 A adapter when the controlled output load exceeds 200 mA, and budget for the combined load and starting current. The stated 1 A output limit does not confirm two simultaneous 1 A loads.

Remove power before changing wiring. Keep DI below DC 28 V, AV within 0–10 V, and AI within 4–20 mA. Do not exceed the stated maxima of 10.7 V on AV and 22 mA on AI.

3. Field Wiring

Follow the labels on the delivered unit. The table describes signal connections, not the physical left-to-right terminal order.

3.1 Digital Inputs

DI1 and DI2 share COM. Choose one compatible common-reference arrangement for the connected sensors.

Signal source	Connection
Dry contact using the RTU supply	COM to supply −; contact between supply + and DI1 or DI2
Powered contact	COM to the external supply −; switched positive signal to DI1 or DI2
PNP three-wire sensor	COM to sensor supply −; sensor output to DI; power the sensor from its rated supply
NPN three-wire sensor	COM to sensor supply +; sensor output to DI; power the sensor from its rated supply

Keep the signal and reference within the 28 V input limit. Because COM is shared, do not mix incompatible NPN and PNP reference arrangements on the two inputs without suitable interface circuitry.

3.2 Digital Outputs

DO1 and DO2 switch the RTU supply voltage to the load. They are voltage outputs, not dry contacts.

1. Confirm that the load voltage matches the RTU supply and its current is within the confirmed output and combined-load limits.
2. Connect the load between DO1 or DO2 and the DO GND terminal.
3. Add suitable transient suppression for inductive loads.
4. Start with a test load. Measure output voltage and verify both on and off states before connecting production equipment.

Use an interposing relay or driver when the equipment requires a dry contact or exceeds the output rating. Confirm startup and communication-loss behavior before leaving the equipment unattended.

3.3 Analog Inputs

Sensor signal	RTU connection	Normal range
Voltage output	Signal to AV; reference to the adjacent GND	0–10 V
Current output	Signal to AI; return to the adjacent GND	4–20 mA

Power the sensor according to its own manual. For a two-wire current-loop transmitter, confirm the complete loop supply and return wiring before connection; the AI input is not a stated sensor power source. Never connect a voltage output to AI or use DO as an analog setpoint output.

3.4 RS485

Connect the equipment's A and B lines to the labeled RTU A and B terminals. Match the serial settings and device protocol. Use twisted-pair cable, with termination and biasing as required by the bus design. Verify polarity from both equipment manuals because A/B naming can differ.

4. Local Configuration

Use the configuration tool and connection procedure supplied for the hardware and firmware revision. The USB connector is documented as a debug/log interface; do not assume it is a universal configuration port.

1. Save the existing settings and record the hardware and firmware versions.
2. Set the radio plan, activation parameters, and device class.
3. Configure the reporting interval and supported state-change reporting.
4. If RS485 is used, set the serial parameters and one test polling command.
5. Save, read back, and verify the settings. Restart only when the tool requests it.

4.1 RS485 Parameters

Parameter	Values
Initial setting	9600 bps, 8 data bits, no parity, 1 stop bit
Baud rates	1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 bps
Data bits	8
Stop bits	1 or 2
Parity	None, odd, or even

For polling, confirm the device address, command bytes, response timeout, and interval. For Modbus RTU, also confirm function code, register address convention, byte order, and scaling. Transparent transport carries serial bytes in LoRaWAN packets; wireless timing and payload limits still apply.

4.2 Timed, Pulse, and Local Control

The product supports timed output, pulse output, and local input-to-output rules on compatible firmware. Before enabling one, record its trigger, delay or pulse duration, output action, priority, and reset behavior. Test conflicting conditions and loss of the radio link using a test load.

Use the supplied command definition. This manual does not assign unverified FPorts, pulse units, or output command bytes.

5. LoRaWAN Commissioning

5.1 Match the Radio Plan

Supported plans are EU433, CN470, EU868, AU915, US915, and AS923. CN470 is the reference deployment plan. Select the hardware variant and, for AS923, its sub-plan before ordering.

Match the gateway receive channels, RTU channel mask, and Network Server regional settings. Also match RX1/RX2 settings for downlinks. A frequency option on the gateway does not establish support in the RTU.

5.2 Register the Device

The RTU uses LoRaWAN 1.0.3. Configure its activation and class on the RTU and in the Network Server device profile.

Activation	Values to match
OTAA	DevEUI, AppEUI/JoinEUI as labeled by the server, and AppKey
ABP	DevAddr, NwkSKey, and AppSKey; register DevEUI where required by the server

OTAA establishes a session through a join exchange. ABP uses provisioned session credentials and has no join exchange.

• Class A: Receive windows follow an uplink. Queue commands on the Network Server before the next reporting opportunity.
• Class C: The powered RTU listens almost continuously except while transmitting and during the Class A receive-window sequence. Downlinks still depend on server scheduling and radio capacity.

5.3 Verify One RTU First

1. Bring the gateway online in the local or remote Network Server.
2. Register the RTU and apply the matching radio and session settings.
3. Restart the RTU only if the configuration procedure requires it.
4. For OTAA, confirm a successful join; for ABP, confirm an accepted uplink and valid frame counter.
5. Confirm a decoded measurement in the application.
6. Test one output command with a test load before adding further devices.

6. Signal and Control Verification

Test	Procedure and acceptance
DI1 and DI2	Apply active and inactive states to each input. Compare the LEDs, reported states, and timestamps.
AV	Apply known voltage values within 0–10 V; compare reported values with a calibrated source or meter.
AI	Apply known currents within 4–20 mA; compare reported values with the reference.
DO1 and DO2	Command each output on and off. Measure the voltage and observe the load; verify the reported state if available.
RS485	Send one known read request. Confirm a valid response and compare the decoded value with the equipment display.
Restart / lost connection	With a test load, check output state and rule behavior against the project requirements.

AV and AI accuracy is specified as ±0.5% of full scale; the reported resolution is 0.001 V or 0.001 mA. Apply the agreed accuracy criteria and reference-instrument tolerance. A radio acknowledgement confirms packet reception, not successful load operation.

7. Application Integration and Handover

Build the decoder from the payload definition supplied for the firmware. LoRaWAN carries bytes; the server may display them as HEX or Base64.

Data	Record in the application contract
DI1 / DI2	State meaning, reporting trigger, and timestamp
AV	Voltage encoding, scaling, unit, and sensor conversion
AI	Current encoding, scaling, unit, and sensor conversion
DO1 / DO2	Command format, response, reported state, and timeout
RS485	Serial framing, command/response association, register types, and error handling
Device status	Heartbeat interval, last-seen time, and any supplied diagnostic fields

Keep the firmware version, radio plan, channel group, class, serial settings, decoder version, output rules, and test results with the device identifier. Store credentials separately. Treat old measurements as stale according to a defined application timeout rather than assuming the last value remains current.

8. Maintenance and Troubleshooting

Back up the configuration before changes. Use firmware supplied for the exact hardware revision and keep power stable during updates. After an update, repeat DI, AV, AI, DO, and RS485 tests for the connected interfaces.

RELOAD short press restarts the RTU; holding it for 5 seconds restores factory settings. Before resetting, obtain the recovery settings and confirm local access. Recheck activation, frame counters, output behavior, and reporting after recovery.

Symptom	Checks
No startup	Supply voltage, polarity, adapter rating, and terminal connection
Restart when DO switches	Combined load and starting current, supply voltage drop, suppression, and adapter capacity
OTAA join fails	Radio plan, channel mask, antenna, gateway connectivity, identifiers, and keys
ABP uplink rejected	Session keys, address, and frame-counter state in the RTU and server
DI state is wrong	COM reference, NPN/PNP or contact wiring, signal voltage, and state mapping
Analog value is wrong	AV versus AI terminal, sensor supply/return, signal range, encoding, and scaling
DO does not operate	Receive-window timing, device class, payload, supply, output wiring, and load current
RS485 response missing	A/B polarity, serial parameters, address, request, timeout, and bus termination
Uplink exists but application is empty	Application routing, FPort, encoding, and decoder version
Intermittent communication	Antenna placement, interference, power stability, reporting load, and server logs

For support, provide the model, hardware and firmware versions, radio plan, device and gateway identifiers, failure time, and redacted logs. Exclude keys and passwords.

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YenGear
Hunan YenGear Tech Co., Ltd.
Room 21014, Building 1, Fudi Xingguang Tiandi, Yingxin Road, Yuhua District, Changsha, Hunan, China
[email protected] · www.yengear.com