Yudian AI-7548D71J7 G5G5S2-24VDC Temperature Regulator

Tipo de producto: DIN-rail 4-channel Independent PID Controlador de temperatura (AI-7xx8 Series Multi-loop Temperature Control Module)

✅ Model Breakdown

AI-7548 + D71 + J7 + G5 + G5 + T2 + -24VCC

1. AI-7548: 4-loop temperature controller, Clase 0.2 exactitud, 4 independent PID control loops, 5-year original manufacturer warranty; accepts 4 thermocouple/RTD inputs
2. D71: DIN rail mount housing, solo 22.5 mm de ancho, dual 7-segment digital display + front panel keys, pluggable bus terminals
3. J7: Universal input board, compatible with thermocouples and RTDs (K/S/J/T/E/B/N/Pt100 etc.), 4 non-isolated input channels, built-in cold-junction compensation for thermocouples
4. 1st G5: Main output module, Dual isolated SSR solid-state relay drive output, 12V/30mA (drives SSR for main temperature regulation)
5. 2nd G5: Auxiliary output module, second set of dual isolated SSR voltage outputs, usable for alarm or auxiliary control

Two G5 modules provide a total of 4 SSR drive outputs, matching the 4 control loops of the AI-7548

6. T2: Opto-isolated RS485 communication module, supports Yudian AIBUS and Modbus RTU protocols; connects to PLC / HMI for reading set temperature, PV/SV and alarm status
7. -24VCC: Controller power supply DC24V (+10%/-15%), power consumption 5VA, not for AC220V supply

📌 Core Technical Specifications

Canales: 4 independent PID loops with APID auto-tune algorithm, each channel with independent SV setting, alarm and filtering

Input signals: k, S, R, mi, j, t, B, N thermocouples; RTD Pt100

Salidas: 4-channel 12V/30mA isolated SSR voltage output (G5 module, for solid state relay SSR driving)

Comunicación: Opto-isolated RS485, Modbus / AIBUS

Exactitud: Clase 0.2; Temperature drift ≤0.01%FS/℃

ciclo de control: 0.48 s

Entorno operativo: -10 ~ +60℃, humidity ≤90% non-condensing

CEM: 6kV EFT surge immunity, suitable for control cabinets, semiconductor burn-in ovens, multi-zone heating platforms, etc..

🔌 Wiring Guidelines (D71+G5 Version)

1. G5 module: OP1~OP4 are output positive terminals, common COM is negative, connect externally to solid-state relays (RSS)
2. Par termoeléctrico: Connect positive wire to INx; all thermocouple negative wires share the common COM terminal
3. 3-wire Pt100: Wire INx, COM and RTDx, supports 2N+1 lead compensation
4. RS485: Terminals A/B, isolated bus; multiple rail-mounted units can share power and communication bus
5. Fuente de alimentación: Never reverse the positive and negative of 24VDC

🧩 Typical Applications

Multi-zone ovens, semiconductor component burn-in testing, multi-station heating stages, multi-zone injection molding temperature control, independent temperature control for laboratory furnaces. Compact DIN rail mounting saves cabinet space.

📎 Replacement & Información de piezas de repuesto

Higher-grade alternative in same series: AI-7648D71 (Clase 0.15 mayor precisión, 8-año de garantía)

Output modification: For 4-20mA current output, replace with X74 module; for NPN transistor output select G71

Comunicación: S2 is opto-isolated RS485 module, the most common communication option for Yudian 7xx8 series for host computer connection

⚠️ Important Notes

G5 is a voltage output module. It cannot directly drive high-voltage contactors, only SSR solid-state relays. Use L-series relay modules if relay contact output is required.

El 4 input channels are non-isolated between channels. Use external signal isolators if large potential differences exist between sensors.

AI-7548D71J7G5G5S2-24VDC Accuracy

Measurement Accuracy Class: 0.2

Especificación: ±0.2%FS ±1 digit

FS = Full Scale of the sensor

When using internal cold-junction compensation for thermocouples, an additional ±1℃ cold-junction error applies

Supplementary Parameters

1. Deriva de temperatura: ≤0.01%FS/℃
2. Display resolution: Selectable 1℃ or 0.1℃ (only for display; internal measurement always 0.1℃)
3. PID control accuracy: Determined by APID auto-tune algorithm. Steady-state temperature fluctuation is normally much smaller than instrument measurement error (affected by sensor, heating system and heat dissipation conditions)

Higher grade model AI-7648 offers Class 0.15 exactitud

AI-7548 (4-channel Multi-loop Temperature Controller) Auto-tune At1~At4 Instructions

The AI-7548 features independent PID for each of the 4 canales. Each channel has dedicated auto-tune parameters: At1, At2, At3, At4 for Channel1~Channel4 respectively. Set parameter =1 to start auto-tune; parameter automatically returns to 0 after completion.

Algorithm: APID Artificial Intelligence PID (Yudian proprietary). During auto-tune, the controller performs 2~3 full on/off oscillations and automatically calculates P/I/D parameters, which are saved permanently.

✅ Preconditions for Auto-tune (Crítico)

1. Verificación de cableado: Sensores, SSR outputs and 24VDC power supply are fully functional; heating circuit can switch normally.
2. modo de control: Set Ctrl of the corresponding channel to APID (recomendado) or nPID. On/Off bang-bang control cannot perform auto-tune.
3. Equipment state: PV near room temperature (cold start). Do NOT start auto-tune at high steady temperature.
4. SV setting: Set SV to approx. 60% of working temperature (p.ej. target 200℃, set SV=120℃).
5. Parameter lock: LOC=0 (unlocked); LOC=808 enables access to all parameters; parameters are locked when LOC>0.

📝 Front Panel Operation Steps

1. Return to main PV/SV display and confirm PV reading is near ambient temperature.
2. Long-press the circle confirm key for 2 seconds to enter parameter menu. Short-press confirm to scroll parameters and locate:

At1: Channel1 auto-tune

At2: Channel2 auto-tune

At3: Channel3 auto-tune

At4: Channel4 auto-tune

3. Change the corresponding Atx value from 0 a 1, press confirm to save.
4. The SV window of that channel flashes At, indicating auto-tune is running.
5. Wait for completion: Time depends on thermal inertia. Minutes for small heating blocks; tens of minutes for large ovens.
6. When At stops flashing and Atx automatically reverts to 0 → auto-tune complete, PID parameters saved automatically.
7. Change SV back to normal process temperature and put into operation.

Recomendación: Tune channels one by one, do not launch auto-tune on all 4 channels simultaneously to avoid thermal crosstalk interference.

⏹ Manually Abort Auto-tune

Locate the corresponding Atx parameter and set value from 1 back to 0 to terminate immediately. No parameters will be saved for this aborted tuning cycle.

💻 RS485 Remote Auto-tune (Modbus/AIBUS)

Host software can write the corresponding Atx register to 1 remotely to trigger auto-tune. Register resets to 0 automatically after tuning finishes.

⚠️ Common Failures & Precauciones

1. Never start AT at stabilized high temperature: Distorted thermal curve yields poor PID parameters, causing overshoot or oscillation.
2. Keep system undisturbed during auto-tune: Do not open doors, activate forced cooling or change load.
3. Retune when operating conditions change: Retune after replacing heater, sensor, SSR or modifying oven insulation / características de carga.
4. Minor overshoot after auto-tune: Fine-tune P/I/D manually, repeated auto-tune is unnecessary.
5. At=10: Output shutoff, not used for normal auto-tune.
6. G5 SSR output module: Controller outputs full amplitude to drive SSR during auto-tune. Ensure heating circuit is safe.

❓ When to Re-run Auto-tune

First commissioning after installation

After replacing thermocouple/Pt100, SSR or heating element

After modifying oven cavity or insulation structure

Large change in process set temperature

Persistent oscillation, heavy overshoot or unstable temperature control

AI-7548D71J7G5G5S2-24VDC Full Parameter Configuration Guide

AI-7548 has independent parameters for 4 canales (CH1~CH4). Each channel has dedicated input INPx, setpoint SPx, Ctrl control mode, P/I/D, Atx auto-tune and alarm parameters. There are also global common parameters (communication Addr, bAud baud rate, LOC parameter lock, etc.).

Configuración de hardware: D71 display head, J7 universal input, dual G5 for 4 SSR outputs, S2 opto-isolated RS485, DC24V supply

1. Front Panel Key Rules (D71 Display Module)

Circle Confirm Key: Long press for 2s to enter parameter menu; short press saves value and jumps to next parameter

Up/Down ▲ ▼: Modify numeric values

Left ◀: Move cursor; long press left key 2s to return previous parameter; Izquierda + Confirm pressed together for quick exit from parameter menu

Timeout protection: 25s without keypress triggers automatic exit. Unsaved changes are discarded.

1. Parameter Lock LOC (Crítico, controls parameter visibility)

LOC permission definition:

1. LOC=808: Full parameter unlock, modify all channel and global parameters, used during commissioning
2. LOC=0: Only EP1~EP12 defined field parameters editable (p.ej. temperature setpoint SP), for normal production
3. LOC=1: View-only for field parameters, no modification allowed
4. LOC≥4: Fully locked, almost no parameters editable (communication read/write is NOT limited by LOC)

✅ Steps to unlock full parameters:

1. On main PV/SV screen, long-press confirm for 2s to enter menu
2. Short press confirm to scroll parameters and find LOC
3. Use up/down keys to set value to 808, press confirm to save; full parameter access is now available

III. Recommended Commissioning Sequence

Paso 1: Sensor Input Configuration (INP1~INP4, independent per channel)

INP = Sensor type code

K-type thermocouple → INP=0

Pt100 RTD → INP=21

j, t, S, B, N thermocouple codes refer to manual

Ejemplo: CH1 K thermocouple, INP1=0; CH2 Pt100, INP2=21

Related parameters:

dPt1~dPt4: Decimal point, 0=1℃ resolution; 1=0.1℃ display (internal measurement always 0.1℃)

SCLx/SCHx: Más bajo / límite superior del rango (normally unchanged for thermocouples)

ScBx: Temperature offset correction for sensor calibration; default =0 normally

Paso 2: Control Mode Ctrl1~Ctrl4 (per channel)

Ctrl=1: APID (recomendado, Yudian AI PID, supports At auto-tune)

Ctrl=2: nPID conventional PID

Ctrl=0: Bang-bang ON/OFF control, auto-tune At not available

This model uses G5 SSR voltage output; APID/nPID is required for continuous PID regulation

Step3: Channel Setpoint SP1~SP4

Target temperature SV for each loop. SP can be modified under LOC=0 without 808 unlock.

Step4: PID & Auto-tune At1~At4

PAG: Proportional band; I: Integral time; D: Derivative time

Atx=1: Start auto-tune of corresponding channel; controller auto-resets Atx=0 after completion

Tune channels one at a time, avoid 4-channel simultaneous AT to prevent thermal interference

Step5: Alarm Parameters (H.ALx high limit, L.ALx low limit, dHAL/dLAL deviation alarm)

H.AL: Absolute high alarm; L.AL absolute low alarm

dHAL: Positive deviation alarm (triggered when PV>SV+deviation), dLAL negative deviation alarm

AOPx: Alarm output definition, assign alarm signal to selected output channel

Step6: Global Communication Parameters (S2 RS485 Modbus/AIBUS)

Addr: Controller communication address (Modbus uses 1 address for the whole unit; AIBUS occupies 4 consecutive addresses)

bAud: Velocidad de baudios (2400,4800,9600,19200,38400). Host and controller baud rate must match.

S2 opto-isolated, bus wiring A/B. No duplicate Addr for multiple controllers on same bus.

1. Two Configuration Methods: Panel Operation + RS485 Host Communication

Method A: Local Setup via D71 Panel (Site Commissioning)

1. Encendido, verify PV display normal and no ORAL input alarm
2. Long press confirm 2s to enter parameter list → Locate LOC and set to 808 for full unlock
3. Configure INP1~INP4 → Ctrl1~Ctrl4 → SP1~SP4 in sequence
4. Set alarm parameters H.AL, dHAL per process requirements
5. Launch At1~At4 auto-tune to obtain PID values
6. After commissioning, set LOC=0 to restrict editable parameters to SP and prevent accidental modification of core settings
7. Press Left + Confirm together to exit menu and return to PV main screen

Method B: Remote Configuration via Modbus RTU (SOCIEDAD ANÓNIMA / PC host)

The S2 module supports Modbus RTU for remote:

Reading PV actual temperature, SV setpoint, PID parameters and alarm status

Remote modification of SP, INP, Ctrl; remote write Atx=1 to trigger auto-tune

Modbus registers start at address 40001; CH1 parameters first, CH2/3/4 follow with offset addresses. LOC lock does NOT block communication access.

1. Common Parameter List (CH1 example; CH2/3/4 use same logic with suffix 2/3/4)

1. Errores comunes & Notas
2. Wrong INP setting triggers ORAL input alarm, temperature reading failure. Always verify INP first after power-up.
3. Ctrl cannot be 0 (bang-bang), otherwise At auto-tune is invalid.
4. G5 is SSR voltage output. No need to change OP output type to current output; cannot drive contactors directly.
5. EP1~EP12: Customize visible parameters under LOC=0. Ejemplo: EP1=SP1, EP2=SP2, EP5=nonE to end list.
6. Parameters only saved after confirmation. Short press confirm to save value; direct exit discards changes.
7. Input channels are non-isolated. Install external signal isolators when large potential differences exist between sensors.

VII. Parameter Backup Recommendation

After full successful commissioning:

1. Manually record critical parameters INP/Ctrl/PID/alarm/communication

2. Read all parameters via Modbus from host software and save project file, enabling fast parameter download for controller replacement