Do you need both DC Circuit Breaker and T-Fuse? From the Mangum manual (below), it sounds like you can get away with the DC Breaker with Overcurrent protection device. Could someone confirm? T-Fuse are hard to find these days.
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For safety and to comply with electrical code regulations, you must install a DC overcurrent protection device in the positive DC cable line to protect your DC cables. This DC overcurrent device can be a fuse or circuit breaker and must be DC rated. It must be correctly sized according to the size of DC cables being used—which means it is required to open before the cable reaches its maximum current carrying capability, thereby preventing a fi re. In a residential or commercial electrical installation, the NEC requires both overcurrent protection and a disconnect switch. If a circuit breaker is used as the overcurrent protection device, it can also be used as the required DC disconnect. For maximum protection, install the circuit breaker (or fuse/disconnect) as near as practical to the batteries. "
If a fuse is used as an overcurrent device, a Class-T type or equivalent is required. This fuse type is rated for DC operation, can handle the high short-circuit currents, and allows for momentary current surges from the inverter without opening. However, because the fuse can be energized from both directions, if it is accessible to unqualifi ed persons, the NEC requires that it be installed in a manner that the power can be disconnected on both ends of the fuse before servicing.
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