Description

The YOKOGAWA YS1700-000/A34 is a high-performance, single-loop digital indicating controller from Yokogawa’s renowned YS1700 series—designed for precise regulation of temperature, pressure, flow, level, and other industrial process variables. This compact 1/8 DIN (96 × 96 mm) unit combines universal input compatibility, advanced PID control algorithms, dual independent outputs, and robust diagnostics in a rugged, panel-mounted housing suitable for demanding environments including chemical plants, power stations, food processing, and pharmaceutical manufacturing.

The /A34 suffix denotes a specific hardware configuration: universal analog input, two relay outputs, and no communication option. This makes the YS1700-000/A34 ideal for standalone control applications where local loop regulation is required without integration into a larger DCS or SCADA system. Despite its simplicity, it features Yokogawa’s proven autotuning technology, heating/cooling (reverse-acting) control modes, and programmable logic functions—enabling complex sequences like ramp/soak profiles or alarm-based interlocks directly within the controller itself.

Built to global safety and environmental standards, the YS1700-000/A34 carries NEMA 4X (IP66) front-panel protection against dust and water jets, and is certified for functional safety up to SIL2 per IEC 61508 when used in appropriate safety loops—making it suitable for burner management or over-temperature shutdown applications.

Technical Specifications

? Note: The “/A34” suffix breaks down as:

• A3: Universal input (TC/RTD/mV/V/mA)

• 4: Two relay outputs (no analog output, no communication)

Main Features and Advantages

✅ Universal Input Flexibility
Eliminates the need for multiple controller models—configure any common sensor type via front keypad or software. Ideal for retrofit projects where field sensors vary.

✅ Dual Independent Relay Outputs
Control two separate devices—e.g., heater (via SSR driver) and cooling fan, or main valve and alarm horn—with independent setpoints, hysteresis, and logic.

✅ Advanced Autotuning & Manual Tuning
Yokogawa’s proprietary tuning algorithm automatically calculates optimal PID parameters, reducing commissioning time. Manual fine-tuning is also supported for expert users.

✅ Ramp/Soak & Program Patterns
Supports up to 9 patterns with 16 segments each for thermal processes like annealing, curing, or sterilization—no external sequencer needed.

✅ High Reliability & Diagnostics
Burn-in tested at factory; includes open-circuit detection, sensor break alarms, and output status monitoring. Relay life exceeds 100,000 operations.

✅ SIL2 Functional Safety Ready
When configured for safety-critical functions (e.g., over-temp trip), the YS1700-000/A34 meets IEC 61508 SIL2 requirements—critical for compliance in boiler or reactor systems.

✅ Simple Local Operation
Full setup via intuitive front keypad with navigation keys and parameter lockout—no laptop or configuration software required for basic use.

Typical Applications

• Temperature Control: Furnaces, ovens, autoclaves, plastic extruders

• Pressure Regulation: Compressor discharge, tank blanketing systems

• Level Control: Chemical dosing tanks with high/low alarms

• Safety Shutdown Loops: Overheat protection in heat transfer systems (SIL2)

• Pharmaceutical Processes: Sterilization cycles with validated ramp/soak profiles

• Food & Beverage: Pasteurization, cooking, chilling with hygiene-compliant mounting

Related Products

• YS1700-000/A11: 4–20 mA input, 4–20 mA output, RS485 communication

• YS1700-000/A22: Thermocouple input, SSR drive output, relay alarm

• UP35A / UP55A: Yokogawa’s newer Green series—successor with color LCD and Ethernet

• YSS1000: Configuration software for YS1700 (optional, not required for basic use)

• YS1700-000/A32: Similar to /A34 but with 1 relay + 1 SSR output

Installation & Maintenance

• Mounting: Install in standard 92 × 92 mm panel cutout; secure with rear brackets.

• Wiring: Use shielded twisted-pair cables for sensor inputs; ground shield at controller only.

• Configuration: Set input type, range, control mode, and output logic via front panel. Password protection available.

• Maintenance: No routine servicing needed. Inspect relays every 2–3 years in high-cycle applications. Replace if contact resistance rises or sticking occurs.

• Calibration: Recommended annually using a precision calibrator (e.g., Yokogawa CA71).