🔍 Key Concepts

• NMEA 2000 power budgeting on a backbone/network • Meaning of LEN (Load Equivalency Number) as a standardized current unit • How device current draw adds up in LENs vs milliamps (mA)

💭 Think About

• If a device label says it draws a certain number of LENs, what total current (in mA) would several such devices represent? • Think about whether 1 LEN should be a large or small amount of current so that many devices can be counted on one network. • Compare the answers: which value would make it practical to express small electronic loads as neat whole-number LENs?

✅ Before You Answer

• Check that 1 LEN value is realistic for small marine electronics (e.g., sensors, displays) rather than big motors or pumps. • Verify that using this value, a network with 50–100 LEN of devices still stays within a reasonable total current for an NMEA 2000 backbone. • Confirm that the unit is defined in milliamps (mA), not amps, and that the decimal place makes sense when multiplied by typical LEN ratings.