Panasonic SQ4-A22-N Safety Chemical Liquid Leak Sensor

Technical Overview

Chemical-resistant safety liquid leak sensor with dual NPN outputs and two-stage detection. PFA enclosure, IP67/IP65 rated, 12-24VDC, SIL3 capable.

Key Features

Designed for chemical liquids, including Sulfuric acid, Hydrochloric acid, Phosphoric acid, Ammonia, Fluorinert™, Galden®, and Hydrofluoric acid.
Features two-stage detection for both incipient and abnormal liquid leaks.
Achieves Category 4, PLe, SIL3 safety requirements when used with the SQ4-C11 controller.
Constructed with a PFA enclosure for superior chemical resistance.
Offers robust IP67 and IP65 protection ratings for harsh conditions.
Equipped with NPN x 2 control outputs with distinct response times (Out 1: 10ms, Out 2: 50ms).
Capable of detecting human error (improper installation) and sensor malfunctions.
Comes pre-wired with a 2m 4-core PFA cabtyre cable.

Technical Specification Matrix

Parameter	Value
Part Number	SQ4-A22-N
Sensing Type	Liquid leak detection, chemical resistant
Sensing Source	Infrared LED (modulated)
Supply Voltage	12 to 24 V DC ±10% (Ripple P-P 10% or less)
Current Consumption	30 mA or less
Control Output	NPN x 2
Output 1 Response Time	10 ms (On when no liquid, OFF when leakage/wrong installation)
Output 2 Response Time	50 ms (ON when normal, OFF when initial detection/accidental leakage)
Operating Temperature	-10 to +55°C (+14 to +131°F)
Storage Temperature	-10 to +55°C (+14 to +131°F)
Ambient Humidity	35 to 85% RH (Storage: 35 to 85% RH)
IP Rating	IP67, IP65 (IEC)
Enclosure Material	PFA
Cable Type	2m 4-core 0.18mm2 PFA cabtyre cable
Safety Category (Standalone)	Category 1, PLc, SIL1
Safety Category (with SQ4-C11 Controller)	Category 4, PLe, SIL3
Physical Weight (kg)	0.05
Dimensions L x W x H (cm)	6 x 1 x 2

Industrial Applications

1. Chemical Processing Plant Leak Detection

Monitoring for leaks of highly corrosive or hazardous chemicals such as acids and ammonia in critical processing areas to prevent environmental contamination and ensure worker safety.

Problem Solved

Provides reliable, early detection and emergency shutdown capabilities for aggressive chemical leaks, safeguarding personnel, equipment, and the environment, justified by its chemical-resistant PFA enclosure, two-stage detection, and SIL3 safety rating.

Chemical resistancePFA enclosureSIL3NPN output12-24VDCIP67

2. Semiconductor Manufacturing Wet Bench Safety

Detecting leaks of etchants and cleaning solutions, including hydrofluoric acid and Fluorinert™, within sensitive semiconductor wet processing stations to maintain product quality and operational integrity.

Problem Solved

Ensures precise and rapid detection of trace amounts of aggressive liquids, preventing costly contamination of wafers and equipment. This is supported by its specific sensing capabilities for Fluorinert™, PFA material construction, and a fast 10ms response time for incipient leaks.

Fluorinert™ detectionPFA10ms response timeIP6712-24VDCTwo-stage detection

3. Pharmaceutical Production Line Spill Monitoring

Safeguarding against accidental spills of active pharmaceutical ingredients (APIs) or cleaning agents in sterile pharmaceutical production environments to prevent product contamination and ensure compliance.

Problem Solved

Maintains stringent cleanliness standards and product integrity by offering precise, chemical-resistant leak detection with robust IP67/IP65 ratings, suitable for frequent washdowns and sensitive processes. Its standalone SIL1 capability ensures basic functional safety.

Chemical resistanceIP67/IP65-10 to +55°C operating tempNPN outputSIL1 (standalone)