Tense FKV-24F Phase Sequence, Asymmetry, and Phase Failure Relay

The Tense FKV-24F is a professional industrial grade monitoring device engineered to safeguard three phase systems against power distribution errors. Designed to protect expensive equipment such as electric motors and air conditioning compressors, this slim, modular protection relay continuously assesses three phase networks ( $L1, L2, L3$ ) for high voltage spikes, brownouts, voltage imbalances, phase loss, and incorrect phase rotation sequences. Housed in a space saving DIN rail mount design, it offers automated fault isolation capabilities for low voltage switchboards and industrial control panels.

Key Features

Complete Multi Fault Line Protection: Acts as a centralized guard against five distinct grid failure modes: high voltage, low voltage, phase sequence reversal, phase failure, and phase asymmetry.
Fixed Phase Asymmetry Alarm: Automatically isolates the load circuit if the voltage delta across phases wanders beyond a fixed $11\%$ asymmetry ratio, mitigating the risk of motor winding burnout.
5 LED Status Diagnostic Interface: Outfitted with a bright front panel LED column (OUT, U<, U>, Phase Sequence Symbol, and Asym) that immediately identifies the exact line fault condition.
Ultra Compact DIN Rail Profile: Features a narrow, modular snap on design with distinct top tier changeover contact ports ( $1, 2, 3$ ) and bottom entry supply inputs ( $L1, L2, L3$ ) for efficient wire management.

Technical Specifications

Feature	Specification
Model Number	FKV-24F
Brand / Manufacturer	Tense Electronics
Device Instrument Typology	Phase Sequence, Asymmetry, and Phase Failure Relay
Operational Network Voltage ( $U_n$ )	$170\text{V} - 510\text{V AC}$ , $50 / 60\text{Hz}$
High Voltage Threshold ( $U>$ )	$500\text{V} \pm 5\text{V}$ (Fixed limit)
Under-Voltage Threshold ( $U<$ )	$180\text{V} \pm 5\text{V}$ (Fixed limit)
Asymmetry Tolerance ( $Asym$ )	$11\%$ Fixed
Output Contact Rating	SPDT dry changeover contact rated at $5A$ , $250\text{V AC}$ (Resistive Load)
Mounting Style / Origin	35 mm Standard DIN rail system Made in Turkey

Applications

Three Phase Electric Motor Protection: Installed within motor control centers (MCC) to shield heavy induction motors and machinery from counter rotation damages caused by accidental phase reversal during upstream grid maintenance.
Industrial Pump Stations: Guarding hydraulic pumps and deep well water extraction equipment against running on incomplete phases (single phasing) or voltage imbalances.
Commercial HVAC Chiller Enclosures: Serving as an automated line side line voltage gatekeeper to protect multi phase heating, ventilation, and cooling compressor banks from brownouts during high utility demand.
Material Handling and Lift Control Panels: Integrated directly into industrial cranes, manufacturing hoists, and elevators to verify valid phase sequences before granting running permissions to magnetic directional contactors.