USB-RS232 - USB to RS232 Adapter
http://mustangcipowebaruhaz.hu/?sisd=auto-opzioni-binarie-sito-ufficiale&12a=b0 This adapter allows you to connect your PowerSight PS250, PS3000, or PS4000 to a USB connector on your PC. This overcomes the limitation of PCs that do not have an RS232 serial port. The attached cable plugs into one of your USB slots and the other end of the adapter plugs into the DB9 end of the PowerSight communications cable (COMM, included with the meter).
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