StandbyCalc
UK standby battery calculator for fire and intruder alarm systems
Screenshots
Features
Intruder Alarms
BS EN 50131 / BS 9263 compliant. Grades 1-4 with automatic standby and alarm period selection. ARC mains-fail signal support.
Fire Alarms
BS 5839-1:2025 compliant. Categories L, M, and P. Occupancy, generator backup, and configurable de-rating factor.
Standalone PSU
Custom standby and alarm periods. 12V or 24V systems. Perfect for signalling devices, access control, and CCTV backup power.
Instant Results
Full calculation breakdown showing the formula, standby load, alarm load, ageing factor, and recommended standard battery size.
PDF Reports
Generate professional A4 reports with full formula working. Add your company branding and logo. Share via email or AirDrop.
Save & Sync
Save unlimited calculations locally. Pro users get iCloud sync across all devices. Swipe to delete, tap to review.
Standards
Calculations follow published British Standards and are compliant with NSI and SSAIB requirements.
Download
Free on the App Store. One-time Pro upgrade for PDF reports, branding, and iCloud sync.
Published by D4N LTD