A low battery causes the unit to emit a tone signal. If this is ignored, the unit's logic sequence will eventually shut it down. Normally, the override key is restricted to the locksmith and possibly to a lockbox used by the fire department for emergencies. Strict key restrictions prevent abuse of the system while providing for backup operation if needed. Operation of e.
Primus lock is easy.
User simply touches key to touch port to activate lock. The touch key and related lock design are both more resistant to abuse and damage than magnetic cards and readers. Magnetic stripes are easily damaged and may wear out quickly. Cards are easily cracked or broken. The metal-encased touch key buttons, however, are resistant to all but the most deliberate damage.