WATLOW ANAFZE CLS216 (216-C20000DF) – 16‑Channel Temperature Limit Controller for Multi‑Zone Safety

The WATLOW ANAFZE CLS216 is a multi-channel high/low limit system designed to safeguard multi-zone thermal processes. From my experience, it typically sits alongside your primary PID controller and acts as the independent watchdog—if a zone exceeds its programmed limit, the CLS216 latches the event and drives a hard relay to put the equipment in a safe state. The 216-C20000DF build code denotes a specific sensor/relay configuration within the CLS216 family; most users treat it as a direct-form-fit swap for an existing CLS216 in tools like diffusion furnaces, environmental chambers, burn-in ovens, and composite curing systems.

Order Placement Process & Guarantees

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

Key Features

• 16-channel independent limit protection – Each zone is monitored against high/low thresholds to help prevent runaway heating or sensor faults from escalating.
• Latching safety relays – When a limit trips, outputs latch until a manual reset; maintenance teams like the clear trip indication and controlled recovery.
• Wide sensor compatibility – Supports common thermocouples (J, K, T, E, N, R, S, B) and 100 Ω RTD in many cases, making retrofits straightforward.
• Dedicated master safety output – You can wire a master interlock to contactors, SCRs, or gas valves to place the system in a safe state quickly.
• Serial integration – RS‑485 serial communications (Anafaze protocol) for supervisory logging, setpoint management, and remote acknowledgement.
• Clear operator interface – Typically provides zone status and trip details at a glance; you might notice fewer nuisance trips once limits are tuned.
• Field‑proven construction – The CLS2xx platform is known for reliable operation in electrically noisy industrial cabinets.

Technical Specifications

Where it fits best

Typical applications include multi-zone ovens and furnaces (heat treat, curing), environmental chambers, semiconductor tools (diffusion, epitaxy), and thermal processing skids. You might notice that in legacy equipment, the CLS216 provides the safety layer while a separate multi-loop PID (like CL16 or F4T) handles control.

Related & Supporting Products

• WATLOW ANAFZE CLS208 – 8-channel version of the same limit platform; ideal when fewer zones are required.
• WATLOW ANAFZE CL16 – 16-loop PID controller for process control; often paired with a CLS216 for independent safety.
• WATLOW F4T – Modular temperature/process controller with flexible I/O; in some upgrades it replaces older CL-series control while retaining the CLS216 for limits.
• WATLOW DIN-A-MITE or POWER SERIES SCR – Power controllers to drive heaters; connect the CLS master limit relay in series with the SCR enable for failsafe shutdown.
• WATLOW thermocouples and RTDs – Matching sensors (J, K, T, Pt100) to keep measurement accuracy consistent across zones.

Installation & Maintenance

• Cabinet environment – Mount in a ventilated enclosure to maintain 0–50 °C ambient; avoid mounting directly above high‑heat SCRs without airflow.
• Wiring practices – Use shielded thermocouple/RTD cable, maintain polarity, and route low‑level sensor leads away from power lines. Ground shields at a single point.
• Interlocks – Wire the master limit relay to your contactor coil or SCR enable; from my experience, adding an E‑stop in series reduces reset confusion after a trip.
• Setup – Verify input type per channel, high/low limits, and latching behavior. Document the 216-C20000DF I/O map before commissioning.
• Routine maintenance – Annual calibration of sensor inputs; exercise and inspect relay contacts; clean vents; review trip logs for nuisance patterns. Firmware updates may be applicable on certain units.
• Spare strategy – Keeping one pre-configured spare on the shelf typically cuts downtime to under an hour in the event of a failure.

Quality & Certifications

• CE compliance and UL recognition are common across the CLS2xx family (specific marks depend on build and date of manufacture).
• RoHS status may vary by production lot on legacy units; we can verify against your required compliance list.
• Manufacturer-standard workmanship backed by a 365-day warranty from shipment.

If you’re matching an existing installation, sharing a quick photo of the nameplate or a config printout helps confirm the exact 216‑C20000DF I/O and power variant. That small step usually prevents surprises during switchover.