Fire Alarm Voltage Drop
Calculate two-wire DC voltage drop, maximum cable length and end voltage, with adjustable limits and a full wire-size comparison.
Your app workspace
- 44 native copper wire-resistance entries at 20°C
- Maximum one-way length and actual end-of-circuit voltage
- Adjustable allowance, current, cable length and source voltage
- Gauge comparisons, worked examples, local projects and backups
Designed for a browser on iPhone, iPad, Android and desktop. Add it to your Home Screen and prepare its files for offline use. Local work is stored on the device you use.
Actual Web App preview. Your inputs, projects or progress are saved in your own workspace on this device.
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Learning and planning tools for educational use.
About this Web App
What does Fire Alarm Voltage Drop include, and what changed from the native source?
Calculate two-wire DC voltage drop, maximum cable length and end voltage, with adjustable limits and a full wire-size comparison. The source 4.4 V allowance is an adjustable historical default, not a universal code limit. Verify listed device voltage limits and permitted conductors. The Web App adds actual cable-length checks, end voltage, wire comparisons and projects.