VIOX FCT18-B/Bt Off-Delay Timer Relay with Retrigger Control Signal

Introduction

The VIOX FCT18-B/Bt is a high-performance interval relay with retrigger control signal designed for precise timing applications in industrial environments. As a professional-grade off-delay timer relay, it offers exceptional reliability, accuracy, and versatility for controlling machinery, equipment, and automated processes across various industries.

What Are Off-Delay Timer Relays?

Timer relays are essential components in industrial control systems that provide simple, reliable, and economical timing solutions. The off-delay timer relay, specifically, maintains its output during the input signal and continues for a predetermined time after the input signal stops. This functionality is crucial for applications requiring controlled shutdown sequences, cooling periods, or continued operation after trigger events.

Key Benefits of Off-Delay Timer Relays

• Controlled Shutdown: Ensures equipment powers down safely and in the correct sequence
• Extended Operation: Maintains power to components after the initial signal ends
• Process Timing: Provides precise timing intervals for critical industrial processes
• Equipment Protection: Prevents damage from sudden power interruptions

VIOX FCT18-B/Bt Series Features

The FCT18-B/Bt series represents VIOX’s commitment to providing high-quality timing solutions with exceptional performance characteristics:

Versatile Timing Functions

The FCT18-B/Bt offers two distinct timing modes:

1. B: OFF-delay – Standard off-delay function that maintains output for a preset time after trigger signal ends
2. Bt: OFF-delay + instantaneous – Combines off-delay functionality with instantaneous output contacts

Exceptional Time Range Flexibility

With time settings spanning from 0.1 seconds to 100 days, the FCT18-B/Bt can accommodate virtually any industrial timing requirement:

• 0.1-1s: For rapid cycle applications requiring precise short-duration timing
• 1-10s: Ideal for standard short-cycle industrial processes
• 0.1-1m: Perfect for minute-based process control
• 1-10m: Suitable for longer process cycles
• 0.1-1hr: For hourly cycle applications
• 1-10hr: Extended hour-based timing control
• 0.1-1day: Daily cycle control for extended processes
• 1-10day: Multi-day timing for long-duration processes
• 3-30day: Monthly cycle applications
• 10-100day: Extended duration timing for seasonal applications

Precise Ratio Settings

Fine-tune your timing requirements with ratio settings from 10% to 100% in 5% increments:

Technical Specifications

Specification	FCT18-B1	FCT18-B2	FCT18-Bt
Input Terminal	A1-A2	A1-A2	A1-A2
Voltage range	AC 230V / DC24V / AC/DC 12-240V	AC 230V / DC24V / AC/DC 12-240V	AC 230V / DC24V / AC/DC 12-240V
Power consumption	AC 3.5VA/ DC 2.0W	AC 3.5VA/ DC 2.0W	AC 3.5VA/ DC 2.0W
Voltage tolerance	-15% ~ +10%	-15% ~ +10%	-15% ~ +10%
Supply indication	Green LED	Green LED	Green LED
Relay indication	Red LED	Red LED	Red LED
Time ranges	0.1s-100days	0.1s-100days	0.1s-100days
Time setting	button	button	button
Time deviation	0.1%	0.1%	0.1%
Repeat accuracy	0.5%	0.5%	0.5%
Temperature coefficient	0.05%/°C, at=20°C (0.05%/°F, =68°F)	0.05%/°C, at=20°C (0.05%/°F, =68°F)	0.05%/°C, at=20°C (0.05%/°F, =68°F)
Output contact	1*SPDT	2*SPDT	1*SPDT+1*SPDT
Rated current	1*16A	2*16A	2*16A
Mechanical life	1*10⁷	1*10⁷	1*10⁷
Electrical life	1*10⁵	1*10⁵	1*10⁵
Ambient temperature	-20 … +60°C / -40 … +85°C	-20 … +60°C / -40 … +85°C	-20 … +60°C / -40 … +85°C
Mounting	DIN rail EN/IEC 60715	DIN rail EN/IEC 60715	DIN rail EN/IEC 60715
IP Rating	IP20	IP20	IP20
Stripping length	7mm (0.28in)	7mm (0.28in)	7mm (0.28in)
Installed altitude	≤2200m	≤2200m	≤2200m
Pollution level	2	2	2
Max cable size	AWG13-20 0.4N·m	AWG13-20 0.4N·m	AWG13-20 0.4N·m
Dimension	90mm×18mm×64mm	90mm×18mm×64mm	90mm×18mm×64mm
Weight	about 90g	about 90g	about 90g
Standards	GB/T 14048.5, IEC60947-5-1, EN6812-1	GB/T 14048.5, IEC60947-5-1, EN6812-1	GB/T 14048.5, IEC60947-5-1, EN6812-1

Output Options

The FCT18-B/Bt series offers multiple output configurations to match your control requirements:

• FCT18-B1: 1CO contact (1×SPDT)
• FCT18-B2: 2CO contacts (2×SPDT)
• FCT18-Bt: 1CO contact + 1 instantaneous contact (1×SPDT + 1×SPDT)

Control Signal Options

• N: NPN control signal
• P: PNP control signal

Common Industrial Applications for Off-Delay Timer Relays

Timer relays like the FCT18-B/Bt provide critical timing functions across numerous industrial applications:

Lighting Control

Off-delay timer relays enable the delayed switching of multiple rows of lamps in production facilities or greenhouses, ensuring proper illumination cycles and energy efficiency.

Motor Control

Star-delta motor starting with changeover delay helps reduce starting current and prevents interphase short-circuits, protecting valuable equipment and extending motor life.

Cyclic Operations

Manage the weekly startup of fans to prevent machinery from sticking, or control the flushing of pipes to keep them clear—ideal for maintenance automation.

Additional Applications

• Control panels: Sequence operations with precise timing
• Pump controls: Prevent dry running and manage fluid levels
• Machine tools: Control operational sequences
• Automatic doors: Manage opening/closing cycles
• Car park barriers: Regulate traffic flow
• Compressor controls: Optimize pressure cycles
• Transportation systems: Synchronize movement
• Industrial refrigeration: Manage defrost cycles
• Packaging machines: Control product handling
• Baking ovens: Manage temperature cycles
• Water and wastewater: Control treatment processes
• Wind energy: Synchronize turbine operations
• Industrial cleaning: Automate cleaning sequences

Advantages of the VIOX FCT18-B/Bt Off-Delay Timer Relay

Versatile Power Supply

With a wide power supply range from 12 to 240 VAC/DC, the FCT18-B/Bt can be integrated into virtually any electrical system without requiring additional power converters.

User-Friendly Setup

Installation is simplified with clear wiring diagrams on the side of the product, reducing setup time and minimizing the risk of connection errors.

Exceptional Accuracy

With a time error less than 0.5%, time deviation of 0.1%, and repeat accuracy of 0.5%, the FCT18-B/Bt delivers the precision timing required for critical industrial processes.

Industrial-Grade Reliability

The strong anti-interference capability ensures consistent operation even in electrically noisy industrial environments where electrical spikes and surges are common.

Compact Design

With dimensions of 90mm×18mm×64mm, the FCT18-B/Bt offers substantial functionality in a compact package, saving valuable space in control panels and electrical enclosures.

Visual Status Indication

• Green LED: Supply indication
• Red LED: Relay activation indication

Monitoring and Protection Features

The FCT18-B/Bt timer relay functions as part of a comprehensive control and monitoring system:

Three-phase Voltage Monitoring

• Voltage monitoring of mobile three-phase equipment
• Protection of personnel and installations against phase reversal
• Monitoring of supply voltage of machines and installations
• Protection against damage caused by unstable supply voltage
• Switching to emergency or auxiliary supply when necessary

Single-phase Current Monitoring

• Monitoring of motor current consumption
• Monitoring of lighting installations and heating circuits
• Monitoring of transportation equipment overload
• Monitoring of locking devices, electromechanical brake gear, and locked rotors

Single-phase Voltage Monitoring

• Speed monitoring of DC motors
• Monitoring of battery voltages and other supply networks

Liquid Level Monitoring

• Protection of pumps against dry running
• Protection against container overflow
• Control of liquid levels
• Detection of leaks
• Control of mixing ratios

Installation and Setup

Wiring Options

The FCT18-B/Bt supports both NPN and PNP control signal configurations:

NPN Configuration

• Connect Un to power supply
• Connect S to control signal
• Output terminals: 11-14(R1) and 21-24(R2)

PNP Configuration

• Connect Un to power supply
• Connect S to control signal
• Output terminals: 11-14(R1) and 21-24(R2)

Dimension Specifications

The compact design allows for easy installation in standard control panels:

• Height: 90mm
• Width: 18mm
• Depth: 64mm

Model Selection Guide

The FCT18 model designation system allows you to specify exactly the right timer relay for your application:

FCT18- B 1 W N

1. Function: B (Off-delay) or Bt (Off-delay + instantaneous)
2. Type of output: 1 (1CO contact) or 2 (2CO contacts)
3. Supply voltage: A (AC230V), D (DC24V), or W (AC/DC12-240V)
4. Control signal: N (NPN) or P (PNP)

Quality Standards

The VIOX FCT18-B/Bt is manufactured to comply with international standards:

• GB/T 14048.5
• IEC60947-5-1
• EN6812-1

Conclusion

The VIOX FCT18-B/Bt off-delay timer relay represents an ideal solution for industrial timing applications requiring precision, reliability, and versatility. With its extensive range of timing functions, exceptional accuracy, and robust design, it delivers consistent performance in demanding industrial environments.

Whether you need precise control of lighting systems, motor starting sequences, or cyclic operations, the FCT18-B/Bt provides the timing functionality required for efficient automation. Its user-friendly setup, compact design, and comprehensive monitoring capabilities make it an essential component in modern industrial control systems.

For applications requiring reliable time-delayed switching to start motors, control loads, or manage processes, the VIOX FCT18-B/Bt off-delay timer relay offers a professional-grade solution that combines performance, durability, and value.