Hi-Speed USB (Universal Serial Bus) 2.0 compliant & backwards compatible with USB (Universal Serial Bus) 1.01.1 Vista compatible Supports Windows Ready Boost Hi-Speed series Easy Plug & Play installation Driverless Powered via the USB (Universal Serial Bus) port. No external power or battery needed
Includes: useful data-management software
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These devices are simply connected directly across the power supply. They have a very high resistance up to the Vm voltage shown in the table below & therefore usually may be ignored but the moment a transient spike appears on the supply line which exceeds Vm the impedance of the device drops immediately to a very low level while it dissipates the unwanted energy. Choose the suppressor to have a Vm voltage equal to or above the voltage of the power supply it is to be connected across. For example both Suppressor 250 Vac & Suppressor 275 Vac can be connected directly across the UK mains supply. Please note that the use of AC in the description is simply an indication of its most likely use. Both types can be used equally in AC or DC circuits up to the Vm stated. Current ratings are for a typical transient pulse where peak current is reached in 8micros & the pulse has decayed to 50 of its peak value after a further 12micros. It is a standard method of rating these devices & is usually described as an 820micros current wave rating. For voltage transient suppressors with low clamping voltages & near instantaneous response times see Table 21 in Semiconductors Section. Type Device Continuous Peak Clampingmarkingvoltage maxcurrentvoltage Vmac Vmdc 250 Vac 250L250V330V2500A650V 25A275 Vac 275L275V369V2500A710V 25 A Both types Average power dissipation 0.4W max Diameter 11.25mm plusmn 1.25mm Lead pitch 7.5mm plusmn 1mm Please note that the use of DC & AC in the description is simply an indication of its most likely use. All types can be used equally in AC or DC circuits up to the Vm stated. ...

These devices are simply connected directly across the power supply. They have a very high resistance up to the Vm voltage shown in the table below & therefore usually may be ignored but the moment a transient spike appears on the supply line which exceeds Vm the impedance of the device drops immediately to a very low level while it dissipates the unwanted energy. Choose the suppressor to have a Vm voltage equal to or above the voltage of the power supply it is to be connected across. For example both Suppressor 250 Vac & Suppressor 275 Vac can be connected directly across the UK mains supply. Please note that the use of AC in the description is simply an indication of its most likely use. Both types can be used equally in AC or DC circuits up to the Vm stated. Current ratings are for a typical transient pulse where peak current is reached in 8micros & the pulse has decayed to 50 of its peak value after a further 12micros. It is a standard method of rating these devices & is usually described as an 820micros current wave rating. For voltage transient suppressors with low clamping voltages & near instantaneous response times see Table 21 in Semiconductors Section. Type Device Continuous Peak Clampingmarkingvoltage maxcurrentvoltage Vmac Vmdc 250 Vac 250L250V330V2500A650V 25A275 Vac 275L275V369V2500A710V 25 A Both types Average power dissipation 0.4W max Diameter 11.25mm plusmn 1.25mm Lead pitch 7.5mm plusmn 1mm Please note that the use of DC & AC in the description is simply an indication of its most likely use. All types can be used equally in AC or DC circuits up to the Vm stated. ...