Safety Brake Rectifier Emits Constant DC Voltage

The Roba-multiswitch, developed for switching safety brakes quickly, is capable of emitting a constantly controlled DC voltage, independent of the mains voltage. This means that complex adaptation of magnetic coils to varying input voltages becomes unnecessary. Overexcitation on switch-on ensures that the connected brakes release extremely quickly.

Two designs are sufficient to cover all mains voltages worldwide, from 100 to 250V AC or 200 to 500V AC, and mains frequencies of 50 to 60Hz. The Roba-multiswitch for the mains voltage range from 200 up to 500V AC is conceived for the operation of safety brakes with 104V DC coils. The constant output voltage is produced using phase segment control. When switched on, the device temporarily (0 to 50ms) emits a bridge voltage, equalling 90 per cent of the applied mains voltage, rectified to the magnetic coil.

After this very short phase, a controlled overexcitation voltage of 180V DC is applied. The overexcitation time - up to the switchover to the operating voltage of 104V DC - can be selected via DIP switch to the levels 0.15s, 0.45s, 1s, 1.5s and 2s. The Roba-multiswitch for mains voltages of 100 to 250V AC works using a controlled overexcitation voltage of 90V DC. The selectable overexcitation times remain the same. The operating voltage (coil nominal voltage) is 52V DC.

Comments

Post a Comment

Popular posts from this blog

What is Class I Division 2?

Image
A Class I Division 2 is a location: (1) In which volatile flammable gases, flammable liquid-produced vapors, or combustible liquid-produced vapors are handled, processed, or used, but in which the liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown of such containers or systems or in case of abnormal operation of equipment, or (2) In which ignitable concentrations of flammable gases, flammable liquid-produced vapors, or combustible liquid-produced vapors are normally prevented by positive mechanical ventilation, and which might become hazardous through failure or abnormal operation of the ventilating equipment. Class I Division 2 Classification Class I Division 2 refers to the ANSI/ISA 12.12.01 standard. This standard was previously UL1604 until UL recommended the newer ANSI/ISA standard be used and that all hazardous location products be certified under this standa...
Read more

FUSE SIZING CONSIDERATIONS FOR HIGHER EFFICIENCY MOTORS

Image
When selecting the proper fuse for short circuit protection in motor starting applications, it is important to not only ensure that the fuse will not nuisance open during motor start up times, but also that the fuse will coordinate as required with overload relays. When sizing fuses between 125% and 150% of the motor nameplate current, several advantages, including ease of coordination with an overload device, a smaller disconnect, and increased short circuit protection from a lower fuse rating, can be achieved. However, if sizing at this level prevents the motor from starting, it may then be necessary to increase the fuse ampere rating and it then becomes important to know the NEC sizing limitations. As of June 1, 2016, the US Department of Energy has mandated that newly manufactured electric motors will need to meet NEMA Premium® efficiency standards. As motor efficiencies increase, motor locked rotor currents can also be expected to increase. In addition to this, with across-the-lin...
Read more

7/8 16UN Connectors that Provide 600 Volts and 15 Amps

TURCK announces new A-Size 3 and 4-pin 7/8 16UN powerfast™ connectors that provide up to 600 Volts and 15 Amps of power. These IP67 rated connectors provide a modular wiring system designed to handle high current applications for machine power distribution, while providing resistance to vibration commonly associated with conveyors, motors and material handling applications. The cordsets are available with a tray rated, exposed run PVC flexlife ® cable, with or without STOOW rating, and 14 AWG wires that allow you to replace hard wiring with a robust, quick disconnect system that saves the time and money spent installing a conduit system. The A-Size powerfast line offers male and female, straight connectors, standard and custom lengths, and pigtails or extensions. To make the system complete, fully encapsulated mating receptacles, with 1/2”-14 NPT mounting threads are available.
Read more