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Voltage Monitoring Relays

Voltage monitoring relays can be designed for use on single-phase AC or DC voltages to protect motors and connected equipment from over-voltage or under-voltage conditions. Three-phase voltage monitoring relays monitor over-voltage and under-voltage conditions, as well as phase loss, phase imbalances and phase reversal.

Schneider Electric Harmony Control Relays monitor and detect abnormal operating conditions concerning current, phase, voltage, frequency, liquid level, temperature, speed and pump control. This information allows users to initiate the necessary corrective actions before serious breakdowns occur. Settings can be configured digitally using the Zelio NFC App. Monitoring parameters can be set precisely to the desired value and time delay can be set to minutes, seconds or milliseconds. Harmony Control Relays are suitable for a wide range of applications including: packaging, lifts, textile, pumping, and water.

Phoenix Contact EMD Monitoring Relays are available for a wide range of monitoring tasks to keep them within limits or to avoid the consequences of errors. The operating states are indicated using colored LEDs. Errors that may occur can be sent to a control system via a floating contact or can shut down a part of the system. Some devices are equipped with startup and response delays in order to briefly tolerate measure values outside the set monitoring range.

Products

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$246.53
Littelfuse TVW9510S0.4S is a compact, reliable, and versatile voltage monitor. It offers a wide input tolerance range of -0.5% and a surge protection level of IEEE C62.41-1991 Level B. With an output load rating of 10 A resistive @ 240 Volts and various termination options, it is suitable for a range of applications. The monitor also features voltage unbalance detection, phase loss detection, and automatic reset functionality, ensuring optimal electrical system performance.
$227.70
Littelfuse TVW6510S0.4S is a 3-phase delta or WYE input voltage monitor with a load rating of 10A resistive @ 125V, 5A @ 250V, and 1/4hp @ 125V. It offers surge protection, voltage detection with delayed trip and automatic reset, and a trip delay range of 10s. It has 0.25 inch male quick connect terminals and operates at an input AC line frequency of 50-100Hz. Its compact design consumes approximately 2W of power and has a response time of ≤200ms for phase loss and phase reversal.
$227.70
Littelfuse TVW575S1M is a 3-phase voltage monitor with 10A resistive load rating. It has 0.25 in. quick connect terminals and operates at a frequency of 50-100Hz. With surge protection and a trip delay of 5s, it offers automatic reset and detects phase loss with a response time of ≤200ms. It supports 3-phase delta or WYE input and has a trip delay tolerance of ±15%.
$227.70
Littelfuse TVW5103S5S is a 3-phase voltage monitor with a load rating of 10 A resistive @ 125 Volts, 5 A @ 250 Volts, and 1/4 hp @ 125 Volts. It features 0.25 in. male quick connect terminals and an input AC line frequency of 50 - 100 Hz. With surge protection and a trip delay of 3 s, it offers reliable voltage detection and automatic reset. It also has a restart delay of 5 s and a response time of ≤200 ms for phase loss and reversal. This voltage monitor is suitable for detecting undervoltage, overvoltage, and voltage unbalance conditions.
$246.53
Littelfuse TVM480A45S5S is a 3-phase voltage monitor with a load rating of 10A resistive @ 240V and various motor ratings. It features 0.25 in. male quick connect terminals for easy installation. With a wide input line frequency range of 50-100Hz and up to 95% non-condensing humidity tolerance, it is suitable for various environments. The monitor offers surge protection, precise trip and reset voltages, and reliable phase loss detection with automatic reset. Trip and restart delays are fixed at 5s, and response time is ≤200ms. The monitor can handle input types of 3-phase delta or WYE with no connection to neutral. Overall, this voltage monitor offers effective and reliable protection for electrical systems.
$246.53
Littelfuse TVM480A100.5S3S is a 3-phase delta or WYE voltage detection device with a 10 A resistive load rating and 0.25 in. male quick connect terminals. It operates at 50-100 Hz AC line frequency with surge protection according to IEEE C62.41-1991 Level B. Featuring automatic reset and trip delay of 5 s, it is suitable for a wide range of applications.
$246.53
Littelfuse TVM460A41S5M is a compact three-phase voltage monitor with male quick connect terminals. It has a 10 A resistive load rating, surge protection, and can handle input line frequencies from 50 to 100 Hz. With its automatic reset and trip delay features, it offers reliable protection against voltage variations. Suitable for use in various industrial applications.
$346.64
Littelfuse PLMU11 is a versatile plug-in voltage monitor with an octal 8-pin termination type. It has a load rating of 10A resistive at 240V and offers surge protection according to IEEE C62.41-1991 Level B. With voltage detection, delayed trip, and automatic reset, it operates on 3-phase delta or WYE systems with no connection to neutral. Featuring adjustable trip delay, voltage unbalance trip points, and a wide input tolerance range, it provides reliable protection against phase loss, phase reversal, undervoltage, and overvoltage.
$182.69
Littelfuse KVM6 is a compact and reliable voltage monitor. It has an output load rating of 8 A resistive @ 120 Volts and 1/3 hp @ 120/240 Volts, making it suitable for various applications. The termination type is 0.25 in. (6.3 mm) male quick connect terminals for easy installation. With an input AC line frequency of 50/60 Hz and a humidity resistance of 95% non-condensing, it ensures optimal performance. Its repeat accuracy is ±0.5% under fixed conditions and ±1% over a temperature range. The insulation resistance is ≥100 and it consumes 2.5 W @ 132 Volts and 4.5 W @ 264 Volts. The reset time is ≤150 ms and it offers surge protection as per IEEE C62.41-1991 Level A. It operates on a single-phase input and has an undervoltage sensing range of 156-199 Volts.
$182.69
Littelfuse KVM4 is a compact and reliable single-phase voltage monitor. It has a load rating of 8A resistive @ 120V and 1/3hp @ 120/240V. The termination type is 0.25 in. male quick connect terminals. It operates at an input AC line frequency of 50/60 Hz and can withstand 95% non-condensing humidity. With a repeat accuracy of ±0.5% under fixed conditions, it ensures precise performance. It has surge protection according to IEEE C62.41-1991 Level A. The undervoltage sensing range is between 78-99V. Its power consumption is 2.5W @ 132V and 4.5W @ 264V, and its reset time is ≤150ms upon power off. The insulation resistance is ≥100.
$1625.30
Littelfuse 601-CS-D-P1 is a versatile product with a Pilot Duty output load rating of 480 VA @ 240 Volts and a General Purpose rating of 10 A @ 240 Volts. It offers accurate protection with repeat accuracy of ±0.5% voltage and ±1% current. With surge protection up to 4 kV and IP20 protection class, it ensures safety. Modbus RTU communication protocol allows easy integration.
$421.87
Littelfuse 50R4003 is a versatile and reliable product suitable for pilot duty (470 VA @ 600 Volts) and general purpose (10 A @ 240 Volts) applications. It features torque termination (7 in-lbs) and wire size compatibility (12-18 AWG). It operates at both 50 and 60 Hz, with delayed timers increased by 20% at 50 Hz. With a wide humidity range, non-condensing (10-95%), it is suitable for various environments. The undervoltage trip voltage is 90% with a delay range of 2-30 s. The maximum input power is 5 and restart delays are 2 s for undervoltage and complete power loss. The undervoltage reset voltage is set at 93%.