The MNBLEEDER is an outdoor enclosure that has one MNLSOB-T1-AC transmitter and will also bleed down the capacitors in many grid tie inverters. This may be needed to reduce the voltage in the PV output circuit fast enough to meet the NEC 2017 requirement of <30 volts within 30 seconds. The MNBLEEDER will work with one or two PV output circuits and is rated for PV circuits up to 1000 VDC and 12 A each. It does require a 90 volt to 300 volt AC source which is also the trigger for rapid shutdown. This enclosure is wall mounted and is 9.92″H x 6.38″W x 4.69″D.
The MidNite Little Shut-Off Box system is a simple rapid shutdown system that does not require any extra wiring between the grid tie inverter and the PV array. One receiver is used with each inverter to meet NEC 2014 and NEC 2017 code up to the end of 2018. One transmitter can be used with up to six strings. To meet the 2017 NEC code starting in 2019 one receiver is installed per module. The transmitter sends a keep-alive signal over the PV output circuit to tell the receivers to turn on. When the transmitter is disconnected from power, or by a separate shut off button, it turns off and the signal is interrupted and the receivers turn off. Safety is enhanced since any time the transmitter is not on, or should fail, the array will be shut down. Restoring power to the transmitter will turn the system back on.