Siebel&Scholl IPS21-35 AD – DIN-rail isolated signal conditioner for stable 4–20 mA and 0–10 V loops

The Siebel&Scholl IPS21-35 AD is a compact isolation and signal-conversion module designed for industrial control panels. From my experience, this series is typically used to convert and isolate common process signals (4–20 mA and 0–10 V) while breaking ground loops and improving EMC robustness on noisy machines. The “-35” points to a 35 mm DIN-rail format, which makes panel integration straightforward in most cabinets. One thing I appreciate is how these modules help standardize wiring across mixed sensor brands—less troubleshooting when you’ve got long cable runs or mixed grounding.

Company’s Order Placement Process and Guarantees

• Warranty period: 365 days
• Delivery time: typically 1 week if in stock; no more than one month at the latest
• Payment: 50% advance payment; full payment prior to delivery
• Express delivery: FedEx, UPS, DHL

We confirm the exact configuration (input/output range and isolation level) before processing, so you receive a unit that matches your panel standards and documentation.

Key Features

• Galvanic isolation – Typically breaks ground loops between field devices and PLC/SCADA, improving noise immunity.
• Signal conversion – Commonly supports 4–20 mA and 0–10 V input/output, allowing sensor-to-controller compatibility without rewiring.
• DIN-rail 35 mm housing – Slim build for crowded control cabinets; easy mounting to EN 60715 rails.
• 24 VDC supply – Standardized panel power; typically low power draw for dense installations.
• Stable accuracy – In many cases delivers steady linearity and low drift suitable for general automation tasks.
• Field-friendly terminals – Screw or pluggable terminals are common on this series, which speeds maintenance.

Technical Specifications

Note: The IPS21-35 AD is part of a configurable series. Specifications below reflect typical configurations we supply; we’ll verify the exact variant before shipment.

Brand / Model	Siebel&Scholl IPS21-35 AD
HS Code	8543.70 (Electrical apparatus with individual functions, NESOI)
Power Requirements	24 VDC nominal (typically 18–30 VDC)
Signal Input/Output Types	Analog: 0/4–20 mA and 0–10 V (factory-configurable I/O)
Isolation	Galvanic isolation between input, output, and supply (typical ≥2.5 kV test)
Communication Interfaces	None (analog pass-through conversion; no bus required)
Installation Method	35 mm DIN rail (EN 60715)
Dimensions & Weight	Compact 35 mm housing; light-weight module suitable for dense panels
Operating Temperature	Typically -20 to +60 °C (industrial environments)

Application Fields

• Machine building – Isolate servo drive references or scale sensor outputs to PLC analog inputs.
• Process automation – Convert 0–10 V transmitters to 4–20 mA loops for DCS/SCADA compatibility.
• Water & wastewater – Stabilize long-run flow/level signals subject to ground potential differences.
• HVAC & utilities – Clean up analog control signals across distributed panels.
• OEM panels – Standardize sensor interfaces to reduce commissioning time across variants.

Advantages & Value

• Reliability – Galvanic isolation reduces downtime from noise, surges, and ground loops.
• Compatibility – One module to bridge 4–20 mA and 0–10 V devices; helpful in mixed-vendor lines.
• Panel efficiency – Narrow DIN footprint; easier retrofits with minimal wiring changes.
• Procurement simplicity – Configurable ranges mean fewer SKUs to stock and manage.
• Technical support – We verify the setting sheet and provide wiring notes before dispatch.

A maintenance lead at a packaging plant told us, “Swapping in the IPS21-35 AD solved a drifting 0–10 V signal we’d been chasing for weeks.” That seems to be a common outcome when long cable runs and mixed grounds are involved.

Installation & Maintenance

• Cabinet environment – Mount on 35 mm DIN rail in a ventilated enclosure; avoid direct heat sources and high-vibration spots.
• Wiring – Use shielded twisted pair for analog runs; ground shields at one end only to prevent loops.
• Polarity & ranges – Verify input/output range selection and polarity before powering; label channels to match your I/O list.
• Separation – Keep high-voltage and motor cables physically separated from analog lines where possible.
• Routine checks – Annually verify zero/span with a handheld calibrator; retighten terminals and inspect for dust buildup.

Quality & Certifications

• CE marking and RoHS compliance are typically available for this series.
• Manufacturer warranty: 12 months (365 days) from shipment.

Recommended Accessories & Supporting Components

• 24 VDC industrial power supply (buffered), sized with 20–30% headroom.
• DIN end-stops and marker tags for neat panel integration.
• Shielded twisted-pair cable for analog I/O runs (4–20 mA / 0–10 V).
• Handheld loop calibrator for commissioning and periodic verification.