Xantrex Technology PROwatt 1000 manual Fuse/Circuit Breaker Sizing Guidelines

Connecting DC Cables

Fuse/Circuit Breaker Sizing Guidelines

Because your batteries can produce thousands of amps, you need fuses or circuit breakers that can safely withstand the short-circuit current they can produce.

To select the correct fuse type and size:

1.Determine the total cold cranking amp rating for your battery(s). (The cold cranking amp rating of each battery is displayed on the battery case. If it is not, contact the battery manufacturer.) For example:

•If you are using one battery to power your inverter and its rating is 500, the total cold cranking amp rating is 500.

•If you are powering your inverter with two batteries, and each has a rating of 500, the total cold cranking amp rating is 1000.

2.Once you have determined the total cold cranking amp rating of your batteries, identify the corresponding Ampere Interrupting Capacity (AIC) of the fuse or breaker required for your system by referring to Table 3-2. (The AIC is the amount of battery short-circuit amperage that the fuse can safely withstand.)

•If the Total Cold Cranking Amps indicate that the AIC is 2,700 amps or less, choose an ANL 150 fuse.

•If the Total Cold Cranking Amps indicate that the AIC is up to 20,000 amps or if you require a “code fuse”, choose a Class T 150 A fuse.1

Table 3-2 Cold Cranking Amps / Ampere Interrupting Capacity

Total Cold Cranking	Ampere Interrupting Capacity
Amps	(AIC)
650 or less	1500
651–1100	3000
over 1100	5000

1.The figures in Table 3-2are based on standards developed by the ABYC (American Boat and Yacht Council).

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