{"product_id":"dh-32-wired-door-contact-nc-magnetic-security-sensor","title":"DH-32 Wired Door Contact – NC Magnetic Security Sensor","description":"\u003ch2 data-start=\"108\" data-end=\"125\"\u003eKey Features\u003c\/h2\u003e\r\\n\u003cp data-start=\"127\" data-end=\"358\"\u003e• Normally Closed (NC) Magnetic Contact\u003cbr data-start=\"166\" data-end=\"169\"\u003e• Reliable Magnetic Reed Switch Detection\u003cbr data-start=\"210\" data-end=\"213\"\u003e• Durable ABS Plastic Housing\u003cbr data-start=\"242\" data-end=\"245\"\u003e• Surface Mount Easy Installation\u003cbr data-start=\"278\" data-end=\"281\"\u003e• Compatible with Alarm \u0026amp; Security Systems\u003cbr data-start=\"323\" data-end=\"326\"\u003e• Suitable for Doors \u0026amp; Windows\u003c\/p\u003e\n\n\u003cp data-start=\"392\" data-end=\"541\"\u003eThe \u003cstrong data-start=\"396\" data-end=\"429\"\u003eDH-32 Wired Door Contact (NC)\u003c\/strong\u003e is a magnetic security sensor designed for alarm systems to detect the opening and closing of doors or windows.\u003c\/p\u003e\r\\n\u003cp data-start=\"543\" data-end=\"842\"\u003eThe sensor includes \u003cstrong data-start=\"563\" data-end=\"619\"\u003etwo components – a magnetic reed switch and a magnet\u003c\/strong\u003e. When the door is closed, the magnet keeps the circuit closed. When the door opens and the magnet separates from the sensor, the circuit breaks and sends a signal to the alarm panel.\u003c\/p\u003e\r\\n\u003cp data-start=\"844\" data-end=\"995\"\u003eThis model operates in \u003cstrong data-start=\"867\" data-end=\"905\"\u003eNormally Closed (NC) configuration\u003c\/strong\u003e, which is commonly used in wired security alarm systems for reliable intrusion detection.\u003c\/p\u003e\r\\n\u003cp data-start=\"997\" data-end=\"1199\"\u003eWith a compact design and strong ABS casing, the DH-32 door contact is suitable for installation on \u003cstrong data-start=\"1097\" data-end=\"1155\"\u003ewooden doors, aluminum doors, metal doors, and windows\u003c\/strong\u003e in residential and commercial environments.\u003c\/p\u003e\r\\n\r\\n\u003c!--zzmv2--\u003e\r\\n\u003cp\u003e\u003cstrong\u003eThe standard surface mount door contact.\u003c\/strong\u003e The DH-32 is a wired magnetic contact that screws onto the door frame with the matching magnet on the door. It is the workhorse of alarm installation: inexpensive, quick to fit, and reliable for years. Where a recessed contact needs drilling into the door edge, this one mounts on the surface in a couple of minutes, which makes it the practical choice for retrofits and for doors you would rather not drill into.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eWhen surface mount is the right answer.\u003c\/strong\u003e Choose it when you are adding an alarm to an existing building rather than installing during construction, when the door is metal or aluminium and drilling is impractical, when the door is hollow core and cannot take a recessed body, or simply when speed matters and appearance does not. Store rooms, godowns, back doors, office interior doors, and shop premises are all typical.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eHow the magnetic contact works.\u003c\/strong\u003e The sensor housing contains a reed switch, two sealed metal contacts in glass, and the other half is a magnet. With the door closed the magnet holds the reed switch in one state; opening the door removes the magnetic field and the switch changes, signalling the alarm panel. Nothing physically moves, so there is no wear, and the sealed switch is unaffected by the dust that is a fact of life in most Pakistani premises.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eNC contact and cable tamper protection.\u003c\/strong\u003e This is a normally closed contact, the standard for security work. With the door shut, the circuit is complete. Opening the door breaks it and triggers the alarm, and so does cutting the cable. That is the point: an intruder cannot disable the sensor quietly by snipping the wire, because doing so produces exactly the same alarm as opening the door. If someone offers you NO contacts for an alarm zone, ask why.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eFitting it well.\u003c\/strong\u003e Mount the sensor body on the fixed frame and the magnet on the door, aligned directly opposite each other, and keep the closed gap comfortably within the rated distance rather than at its outer limit. Fit on the hinge side edge where practical, because that part of the door moves least and holds alignment best. On metal doors and frames, if detection becomes unreliable, mount both halves on thin non-metallic spacers to lift them off the steel, since metal distorts the magnetic field.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eAlignment causes nearly every callback.\u003c\/strong\u003e When a contact stops working properly, the sensor has rarely failed. Doors settle on their hinges, timber swells in monsoon humidity and shrinks in dry heat, and a contact fitted at the edge of tolerance drifts out of range. Fitting centred, and re-checking a few weeks after installation, prevents most problems.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eCabling and connecting to the panel.\u003c\/strong\u003e Run the cable from the frame side, never to the moving door leaf, and keep it inside conduit. An exposed contact cable is both a durability weakness and a security one. Terminate on an alarm panel zone with the correct end of line resistor if your panel monitors circuit integrity, and label the cable at the panel so future maintenance is simple.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eNo batteries, no WiFi dependency.\u003c\/strong\u003e A wired contact takes its power from the alarm panel, so there is nothing to replace and nothing to quietly go flat. It does not need a router, WiFi, or internet, which means the door stays monitored during load shedding for as long as the panel has its backup battery. That is the main practical argument for wired contacts over wireless sensors on doors that matter.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eWired or wireless?\u003c\/strong\u003e Use wired where the door is part of a real security system that must keep working regardless of connectivity, and where you can run cable. Use a wireless Tuya sensor where you want phone notifications, cannot run cable, or are renting. Many premises sensibly use wired contacts on perimeter doors and wireless sensors on internal ones.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eHow many do I need?\u003c\/strong\u003e One per door, covering every external door and any internal door protecting stock, cash, or records. Contacts are among the cheapest parts of an alarm system, and an uncovered door is simply the route an intruder will take.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eWill it work on a metal door?\u003c\/strong\u003e Usually yes, with non-metallic spacers if needed. For steel rolling shutters, use a dedicated shutter contact instead, which is built for the wider and less consistent gap.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eDoes it need its own power supply?\u003c\/strong\u003e No. It is powered by the alarm panel it connects to.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eWhat is the difference from the recessed DH-35 and DH-36?\u003c\/strong\u003e Those fit inside the door and are invisible when closed, which looks better and resists tampering, but require drilling. This one mounts on the surface and installs far faster.\u003c\/p\u003e\r\\n\u003cp\u003e\u003cstrong\u003eBuying from ZZ Marts.\u003c\/strong\u003e In stock at our Karachi (Saddar) and Lahore stores with nationwide delivery, supplied by Zam Zam Traders, trading in security hardware since 2005. We also stock recessed contacts, rolling shutter contacts, wireless Tuya door sensors, alarm panels, sirens, relay modules, and cabling. Tell us how many doors you are covering and what panel you are using, and we will quote the complete job.\u003c\/p\u003e","brand":"ZZ Marts","offers":[{"title":"Default Title","offer_id":52827975582008,"sku":"DH-32","price":550.0,"currency_code":"PKR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1012\/3932\/4984\/files\/Magnetic-door-sensors-and-screws-set.png?v=1787211282","url":"https:\/\/zzmarts.com\/products\/dh-32-wired-door-contact-nc-magnetic-security-sensor","provider":"ZZ Marts | Zam Zam Traders","version":"1.0","type":"link"}