Nivotester FTL325N

Summary

Product Identification

• Product Name: Nivotester FTL 325 N
• Type: Single channel and three channel isolating amplifier with NAMUR input

Application

• Level limit detection in liquid tanks and hazardous areas.
• Suitable for FM / CSA Division 1 (Zone 0 or Zone 20) measuring sensors.
• Liquid detection in pipes for dry running protection for pumps.
• Over-spill protection for tanks with combustible or noncombustible liquids dangerous to the environment.
• Two-point control and level limit detection with one switching unit.

Features and Benefits

• Intrinsically safe signal circuits (FM IS) for use in explosion hazardous areas.
• High functional safety through line monitoring and corrosion monitoring on tuning forks of Liquiphant M and Liquiphant S (high temperature) measuring sensors.
• Compact housing for series installation on standard rails.
• Simple wiring with plug-in terminal blocks.
• NAMUR interface to EN 50227 (DIN 19234; NAMUR) or IEC 60947-5-6.

Functionality

• The Nivotester supplies a DC voltage to NAMUR-specified sensors and transfers a control current that ranges from < 1.2 mA to > 2.1 mA depending on the switching status.
• The unit measures and evaluates this control current.
• A level alarm relay signals if the measuring sensor is covered or free.
• Faults, such as line interruption or short circuit, are also indicated.
• Fail-safe circuit options allow the relay to operate in a de-energized state for maximum or minimum fail-safe conditions upon fault or power failure.
• Function monitoring system with LED indication and relay de-energization upon fault.

Measuring System

A measuring device consists of one to three measuring sensors, a Nivotester unit, and control or signal devices. Compatible sensors include:

• Liquiphant M with FEL 56 or FEL 58 electronic inserts.
• Liquiphant S (high-temperature) with FEL 56 or FEL 58 electronic inserts.
• Any sensors specified to NAMUR or contact switches with an appropriate resistance circuit.

Input Parameters

• Input for FTL 325N: Galvanically isolated from power supply and output.
• Protection Type: FM Intrinsically Safe, Class I, II, III; Division 1, Groups A-G. CSA Intrinsically Safe, Class I, II, III; Division 1, Groups A-G.
• Connectable Measuring Sensors: Liquiphant M (FTL 50/51, FTL 50 H/51 H, FTL 51 C), Liquiphant S (HT) (FTL 70/71), sensors specified to EN 50227 or IEC 60947-5-6, and contact switches with appropriate resistance circuit.
• Measuring Sensor Power Supply: Supplied by the FTL 325 N Nivotester.
• Connecting Line: Two-wire, shielding not required.
• Line Resistance: Maximum 25 Ω per wire.
• Signal Transmission: Current signal on power supply line.
• Control Current Range: < 1.2 mA / > 2.1 mA.
• Line Interruption Monitoring: < 200 µA.
• Short-Circuit Monitoring: > 6.1 mA (can be switched off).

Output Parameters

• Relay Output per Channel: One potential-free relay contact for the level alarm.
• De-energized Current Safety Circuit: Functionality depends on electronic insert settings and Nivotester error current signal selection.
• Switch Delay: Approximately 0.5 seconds.
• Switching Power:
  • AC version: Maximum 253 V~, 2 A~, 500 VA at cos ϕ ≥ 0.7.
  • DC version: Maximum 40 V=, 2 A=, 80 W=.
• Life: At least 10⁵ switching operations at maximum contact load.
• Function Displays: LEDs for operation, level alarm, and fault.
• Fault Signal: See official PDF for details.

Electrical

• Power Supply:
  • AC version: 85 to 253 VAC, 50/60 Hz.
  • DC version: 20 to 60 VDC.
• Power Consumption:
  • AC version: Maximum 1.75 W (one channel), 2.25 W (three channel).
  • DC version: Maximum 1.2 W (one channel at 20 V), 2.25 W (three channel at 20 V).
• Setting Time/Length: Approximately 10 to 20 seconds after power supply is switched on.
• Galvanic Isolation: All input and output channels and relay contacts are galvanically isolated from each other.

Mechanical / Hydraulic

• Housing Material: Polycarbonate, light grey (RAL 7035).
• Front Cover Material: Polyamid PA6, blue.
• Installation: On top-hat DIN rail, 35 x 7.5 mm or 35 x 15 mm to EN 50022.
• Weight: Approximately 148 g (single channel), 250 g (three channel).
• Connection Terminals: Screw terminals for sensor power supply, limit value relay, fault signal relay, and power supply.
• Connection Cable Cross Section: Maximum 2.5 mm² (single core) or 1.5 mm² (two core).
• Dimensions: See official PDF for detailed dimensions.

Operating Conditions and Installation

• Operating Location: Unit must be housed in a cabinet outside explosion hazardous areas. Optional NEMA 4 (IP 65) protective housing available.
• Installation Position: Mount vertically on a DIN top-hat rail.
• Ambient Temperature:
  • Single installation: -20°C to +60°C (-4°F to +140°F).
  • Rail mounting, without gaps: -20°C to +50°C (-4°F to +122°F).
  • Storage temperature: -20°C to +60°C (-4°F to +140°F).
  • Installation in protective housing: -20°C to +40°C (-4°F to +104°F).
• Climatic Class: 3K3 and 3M2, according to EN 60721-3-3.
• Ingress Protection: NEMA 1 (IP 20).
• Electromagnetic Compatibility (EMC): Interference emission to EN 61326, Class B apparatus; interference emission to EN 61326, Appendix A (industry) and NAMUR Recommendation NE 21.

Certificates and Approvals

• CE mark.
• FM approved intrinsically safe, Class I, II, III; Division 1, Groups A-G.
• CSA intrinsically safe, Class I, II, III; Division 1, Groups A-G.
• EN 50227 (DIN 19234; NAMUR) or IEC 60947-5-6.
• EN 60529, EN 61010, EN 61326.

Accessories

• Protective housing, NEMA 4 rated (IP 66) with integrated top-hat rail. Dimensions: 180 x 182 x 165 mm (7.09” W x 7.17” H x 6.50” D). Part Number: 52010132.

Disclaimer: This summary is based on extracted text and may miss figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror