Work it out.
Calculators
Rigging: working load limit (WLL)
WLL = brudstyrke / designfaktor
Power consumption and the 16 A limit
Effektloven P = U · I
Sound: attenuation with distance (free field)
Invers kvadratlov: ΔL = 20·log10(r2/r1)
3-phase power (CEE power supply)
Effektloven for 3-faset system: P = √3 · U · I · cosφ
Voltage drop in an extension cable
DS/HD 60364-5-52 (maks. 3% belysning / 5% andet forbrug)
Cable reel: load when coiled vs. uncoiled
Producentdata (kabeltromlens mærkeplade)
Generator sizing (kVA)
Tilsyneladende effekt: S = P / cosφ
Projector: throw distance and throw ratio
Producentdata (projektorens kasteforhold/throw ratio)
Screen: recommended viewing distance
SMPTE EG-18 / THX (anbefalet visningsvinkel)
Light beam: spread and coverage area
Geometri (trigonometri) — vinkler ift. ETC Source Four-linsetuber
DMX: fixtures per universe
DMX512-A / USITT (512 kanaler pr. universe)
Rigging: load distribution between two suspension points
Statik (momentligevægt)
Loudspeaker: required peak power (headroom)
Audio engineering (crest factor — gængs branchepraksis)
SMPTE timecode to seconds
SMPTE 12M (tidskode)
Battery runtime for a wireless microphone
Producentdata (batteri-mAh/strømforbrug)
Bridle: force in the two legs
Statics for symmetrical bridle, T = W · L / (2 · H) (H. Donovan: Entertainment Rigging) · technical annex: rigging equipment handled safely
Delay loudspeaker: delay time
Speed of sound c ≈ 331.3 + 0.606 · T m/s · precedence effect (Haas) · technical annex: sound equipment at advanced level
LED screen: resolution, cabinets and power
Manufacturer's cabinet data (pitch, dimensions, W/m²) · eye's resolution 1 arcminute · technical annex: video technology equipment
Tools that work in all subjects
Whatever your programme is called, these tools calculate the same — Pythagoras, area, percentages and units are not tied to one trade.
- Pythagorasa² + b² = c²Find the missing side, set out a right angle, check whether a room is square, and find the space diagonal.
- Area and perimeterm²Rectangle, triangle, trapezium, circle and composite shapes — area and perimeter.
- Volume and surface aream³ · lBox, cylinder, cone, sphere, pyramid, prism, pipe and frustum — also in litres.
- Percent%Percentage of, how many per cent, percentage change, discount and VAT.
- Scale and ratios1 : 50From drawing to reality, area and volume to scale, the rule of three and dividing in a ratio.
- Unit convertermm ↔ mFrom mm to km, Pa to bar and kB to GB — with the unit staircase.
- Time calculations and the clockt : minTime between two clock times, add time, and 1.75 h = 1 h 45 min for the timesheet.
- Slope and fall% · ° · 1:xFall from level to level, in per cent, per mille, degrees and mm per metre — and the height difference.
- Material consumption including wastem² + %Boards, paint, battens at c/c spacing and packs — for a composite surface or a whole room, with waste.