Calculators
PoE budget, CCTV storage, pixel density, fire alarm batteries, PA amplifiers, fibre loss, and voice bandwidth.
Open calculators →Checklists
12 printable checklists for surveys, commissioning, maintenance, and safety.
Browse checklists →Quick reference
14 cards: pin-outs, colour codes, PoE classes, SIP codes, fire alarm figures, and more.
View cards →Field tips
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Nurse call
Patient calls are cancelled only at the point of call. That proves someone actually attended.
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Integration
Life-safety functions must never depend on the BMS or the IT network. Hard-wire fire alarm door releases.
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Analog CCTV
Rolling hum bars on an analog camera almost always mean a ground loop. Isolate the camera or fit a ground-loop isolator.
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Analog CCTV
CCTV coax is 75 Ω (RG59/RG6). RG58 is 50 Ω and causes ghosting.
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PBX
Emergency numbers must work with and without the outside-line prefix, from every phone.
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Networking
Rising CRC errors on a port almost always mean cabling or duplex problems, not a faulty switch.