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Monitoring Relays

Monitoring relays are specialized devices designed to monitor specific electrical parameters, ensuring reliable protection and control of equipment and systems. These relays provide valuable functions such as phase sequence monitoring, voltage monitoring, phase failure detection, current monitoring, and more. They are widely used in various applications and industries to safeguard electrical systems, prevent damage, and minimize downtime.

Voltage monitoring relays are a common type of monitoring relay used to monitor and protect against voltage-related issues. They can detect overvoltage and undervoltage conditions, ensuring that electrical equipment operates within the specified voltage range. These relays provide reliable protection by quickly detecting voltage anomalies and initiating appropriate actions to prevent equipment damage or failure.

Current monitoring relays are another important category of monitoring relays. They continuously measure electrical currents and provide alerts or trigger actions if current levels exceed predefined thresholds. This helps protect equipment from overcurrent conditions, preventing overheating and potential damage. Current monitoring relays are often used in motor control applications to ensure the safe and efficient operation of motors.

Products

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$175.57
Littelfuse TCSHAB is a current sensor with a steady state output load rating of 1 A and inrush rating of 10 A. It features 0.25 in. (6.3 mm) male quick connect terminals for easy termination. With a sensor hole size of 0.36 in. (9.14 mm), it can accommodate up to #4 AWG THHN wire. The sensor has a response time of ≤200 ms for overcurrent and ≤1 s for undercurrent. It has a sensor range of 2-20 A, adjustable with a guaranteed range, and a maximum steady state rating of 50 A. The sensor is toroid type and requires properly insulated wiring. The output voltage ranges from 24-240 volts with a voltage drop of approximately 2.5 V. Humidity up to 95% non-condensing is tolerated. The insulation resistance is ≥100 ohms, and the dielectric breakdown is ≥2000 terminals to the mounting surface. The burden is ≤0.5 VA.
$175.57
Littelfuse TCSHAA is a current sensor with a range of 2-20 A, adjustable within the guaranteed range. It has a response time of ≤200 ms for overcurrent and ≤1 s for undercurrent. The sensor has a 0.36 in. (9.14 mm) sensor hole and 0.25 in. (6.3 mm) male quick connect terminals for easy installation. It operates between 24-240 Volts with a voltage drop of ≅2.5 V and a burden of ≤0.5 VA. The sensor is designed for use with #4 AWG (21.1 mm²) THHN wire and has a dielectric breakdown of ≥2000 terminals to mounting surface.
$175.57
Littelfuse TCSH2B is a current sensor with a 2A fixed range and 50A maximum rating. It has quick connect terminals for easy installation and a sensor hole size of 0.36 inches. The sensor operates with a response time of ≤200ms for overcurrent and ≤1s for undercurrent. It has an output voltage range of 24-240 Volts and a voltage drop of approximately 2.5V. With a compact design and high insulation resistance, it is reliable and suitable for various applications.
$175.57
Littelfuse TCSH2A is a current sensor with a fixed range of 2 A, a maximum range of 50 A turns, and a reset at approximately 95% of the actuate current. It has a response time of ≤200 ms for overcurrent and ≤1 s for undercurrent. The sensor uses a toroid, through-hole wiring system and requires properly insulated wires. It has a termination type of 0.25 in. (6.3 mm) male quick connect terminals, and a sensor hole size of 0.36 in. (9.14 mm) for up to #4 AWG (21.1 mm²) THHN wire. The output load rating is 1 A steady state and 10 A for inrush. The output voltage range is 24 - 240 Volts, with a voltage drop of approximately 2.5 V. The product is humidity resistant up to 95% non-condensing. It has an insulation resistance of ≥100 and a dielectric breakdown of ≥2000 terminals to mounting surface. The product has a burden of ≤0.5 VA.
$175.57
Littelfuse TCSGAB is a current sensor with a 2-20 A adjustable range and a response time of ≤200 ms for overcurrent and ≤1 s for undercurrent. It has a sensor hole size of 0.36 in. and a termination type of 0.25 in. male quick connect terminals. The sensor operates at an output voltage of 3-50V DC and has a low burden of ≤0.5 VA.
$175.57
Littelfuse TCSGAA is a compact current sensor with a male quick connect termination for easy installation. It has a wide current sensor range of 2-20 A and a maximum output voltage of 50 Volts (DC). With a response time of ≤200 ms for overcurrent and ≤1 s for undercurrent, it guarantees reliable and quick protection. The sensor is suitable for up to #4 AWG wire and has a low burden of ≤0.5 VA. With its toroid sensor type and 95% non-condensing humidity resistance, it ensures accurate and durable performance.
$175.57
Littelfuse TCSG2A is a current sensor with a 2 A fixed range and a maximum of 50 A. It features quick connect terminals and a sensor hole size of 0.36 in. The sensor operates on a voltage range of 3-50 Volts DC with an output voltage drop of approximately 1.2 V. With a response time of ≤200 ms for overcurrent and ≤1 s for undercurrent, it offers reliable performance.
$101.10
Littelfuse PHST-38QTN is a probe holder specifically designed for liquid level probes. It is suitable for use in steam pressure environments of up to 240 PSI. With its high durability and functionality, it ensures accurate and reliable monitoring of liquid levels in various applications.
$266.77
Littelfuse PC-200-LLC-GM is a versatile load controller with a Pilot Duty output load rating of 480 VA @ 240 Volts and a General Purpose load rating of 10 A @ 240 Volts. It features torque termination for easy installation with 12 - 22 AWG solid or stranded wires. With an adjustable sensitivity range of 4.7 - 100 Ohms, pulse-sensing technology, and a debounce time delay of 2 seconds, this controller ensures precise and reliable operation. Suitable for 50/60 Hz AC line frequency, it can be used in a wide range of applications.
$266.77
Littelfuse PC-200-LLC-CZ is a versatile product suitable for pilot duty and general purpose applications, delivering a load rating of 480 VA at 240 Volts and 10 A at 240 Volts respectively. With torque termination of 12 in-lbs. and accepting 12-22 AWG solid or stranded wires, it caters to a wide range of installations. Featuring an input AC line frequency of 50/60 Hz (50 Hz increases all delay timers by 20%), it ensures efficient operation. With 10-95% non-condensing humidity tolerance as per IEC 68-2-3, it proves resilient in diverse environments. Other notable features include a maximum input power of 5, a sense voltage of 5 Volts (DC) pulsed (probe), a 2-second debounce time delay, and adjustable sensitivity ranging from 4.7 to 100 Ohms.
$938.02
Littelfuse PC-105 is a versatile device with a torque termination type. It has a pilot duty output load rating of 480 VA at 240 Volts B300 and a general purpose rating of 7 A at 240 Volts. It supports wire sizes ranging from 12 to 20 AWG. With a 50/60 Hz input AC line frequency, it offers a maximum input power of 4 units. Its sense voltage is 5 Volts (DC) and it operates in sensor mode with a 1 relay latched / time delay output. The time delay option ranges from 2 to 255, making it suitable for lag pump delay.
$350.88
Littelfuse PC-102CICI-LT is a versatile control relay with a pilot duty output load rating of 180 VA @ 120 Volts C150 and a general-purpose output load rating of 5 A @ 240 Volts. It features a torque termination type of 6 in-lbs for easy installation with 12-20 AWG wire compatibility. With an input AC line frequency of 50/60 Hz and a maximum input power of 2, it offers reliable performance. The sense voltage is 5 Volts (DC) pulsed with selectable sensitivity options for TEMP input and adjustable SEAL input. The input logic can be direct or inverted.