... -bit industrial-strength ARM processor, faster than MCS51,Access authorization,circuit board, D100(Multiple access control)Access control profileIs a the ... of the card reader with over-current protection, even short circuit card reader power will not harm to the normal operation ... - 485 card reader to controller distance500mWorking voltage10~18V DC(Suggest 12 v)working current< 500mASize190mm× 140mm