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• + [PRODUCT] Smoke Alarm HM-638PH series
• + [QUESTION] What’s the reason that i can’t interconnect the HM-638PHM-AC when i cut off the AC power supply and use battery only?
• + [QUESTION] What’s the wall penetration distance and maximum distance of your HM-638PHW smoke alarm?
• + [QUESTION] What thickness wire do you recommend for interconnected smoke alarm HM-638PHW-AC/HM-638PPHM-AC?
• + [QUESTION] When connect HM-638PHM-AC with 120V wire,there will be 1W power consumption even the switch is turned off,what’ the reason?