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 sends field measurements and RS485 data through a LoRaWAN gateway and Network Server to an application. Downlinks control its two voltage outputs and firmware-supported serial and configuration functions.

The analog inputs have fixed roles: AV measures 0–10 V and AI measures 4–20 mA. Label wiring and application records with these terminal names.

Prepare the RTU, antenna, DC supply, field wiring, and a gateway with matching radio settings. Commissioning also requires:

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

Store keys and passwords in the project credential store. Use the configuration guide and command definitions for the installed firmware.

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. Inspect the 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 output loads exceed 200 mA. Size the supply for the RTU, combined load, and starting current. Check the per-channel and combined output ratings; the stated 1 A limit does not specify 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

Locate terminals by the unit labels; their physical order may differ from the wiring table.

3.1 Digital Inputs

DI1 and DI2 share COM. Use a common reference compatible with both 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. Mixed NPN and PNP sensors need suitable interface circuitry if their COM references are incompatible.

3.2 Digital Outputs

DO1 and DO2 switch the RTU supply voltage to the load.

1. Check load voltage against the RTU supply and current against the confirmed per-channel and combined 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 a relay or driver for equipment that needs a dry contact or exceeds the output rating. Test startup and communication-loss behavior before unattended operation.

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 sensors as specified in their manuals. For a two-wire current-loop transmitter, check the complete loop supply and return wiring; provide sensor power separately unless the supplied wiring guide specifies otherwise. Wire voltage signals to AV and current signals to AI. Use an external analog-output device if an analog setpoint is required.

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 supplied configuration tool and connection procedure for the hardware and firmware revision. USB is a debug/log interface; use it for configuration only if the supplied procedure supports that connection.

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 and read back the settings. Restart if the tool prompts you.

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, set the device address, command bytes, response timeout, and interval. For Modbus RTU, check the function code, register address convention, byte order, and scaling against the equipment manual. Transparent transport carries serial bytes within LoRaWAN timing and packet-size limits.

4.2 Timed, Pulse, and Local Control

Compatible firmware supports timed output, pulse output, and local input-to-output rules. Record the trigger, delay or pulse duration, action, priority, and reset behavior. Use a test load to check conflicting conditions and radio-link loss.

Use the firmware's command definition for FPorts, pulse units, and 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 gateway receive channels, the RTU channel mask, and server regional settings, including RX1/RX2 downlink parameters. Select the RTU's hardware-supported plan even if the gateway offers other options.

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, look for a successful join. For ABP, check for an accepted uplink and valid frame counter.
5. Compare a decoded application value with the field measurement.
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 ±0.5% of full scale, with reported resolution of 0.001 V or 0.001 mA. Account for reference-instrument tolerance when checking accuracy. Verify output operation at the load; a radio acknowledgement confirms packet reception.

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	Application definition
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

Record the firmware, radio plan, channel group, class, serial settings, decoder version, output rules, and test results with the device identifier. Store credentials separately. Define a freshness timeout so the application marks old measurements as stale.

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.

A short RELOAD press restarts the RTU; holding it for 5 seconds restores factory settings. Save recovery settings and arrange local access before resetting. After recovery, recheck activation, frame counters, output behavior, and reporting.

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