MidNite Classic SL User Manual

Classic SL owner’s manual REVB 2056
18 | P a g e x x - xxx- x x R E V : A
The USB cable, BTS cable and auxiliary input/output cables should run in a different conduit to preserve
their signal. When installing the Classic in a MidNite E-Panel, it is acceptable to run all wiring through the
same knockout hole. It is legal to run signal and power wires together as long as all wiring is listed for the
highest voltage to be encountered. (Follow all local code)
Current Rating
The Classic limits the output current based on the model you have.
The Classic current ratings are:
Classic 150-SL - 96 amps maximum
Classic 200-SL - 79 amps maximum
Classic 250-SL - 62 amps maximum
Over Current Protection
The Classic must have over current protection to protect wiring from over current events. A means of
disconnect must be installed on the DC in and DC out of the Classic. Consult your local codes to
determine over current ratings. The breaker between the battery bank and the Classic must conform to
UL489. The breaker between the DC source and the Classic must conform to UL1077 or UL489. The
NEC requires 1.56 times short circuit current for PV over current protection. This is reduced to 1.25 times
when using a breaker rated for continuous duty. All MidNite Solar breakers are hydraulic/magnetic and
are rated for continuous duty (100% rating). No de-rating is required for the output breaker when using
MidNite Solar breakers.
PV in particular will be capable of producing more current than its name plate rating in extreme situations
so the safe minimum wire size should be selected for the PV array maximum short circuit current. Please
consult PV manufacturer for specifications. The US National Electrical Code requires 1.56 times the PV
short circuit current for wire size on the PV input. Output wire size follows the NEC guidelines. Typical
wire size for output is 6AWG for the Classic 250-SL and 4AWG for the Classic 200-SL and 150-SL but
check all de-ratings for your wire type and installation method.
Long Distance Wire Runs
The Classic offers some unique opportunities if you are faced with longer than normal wire runs between
the DC source and the Classic. The Classic comes in 3 input voltage ranges letting you design a DC
source at a higher voltage if it is beneficial. For example let’s say you have a 300 ft run from a PV array to
the Classic. You could wire for an open circuit voltage close to 250vdc accounting for the coldest
temperature you will encounter. This will allow you to run a smaller gauge wire than with a lower voltage
charge controller. The efficiency of a high voltage Classic is less than the lower voltage versions, so you
need to weigh the benefit. If this sounds too complicated use this rule of thumb in selecting the proper
Classic. PV runs up to 100 feet, use the Classic 150, runs up to 180 feet, use the Classic 200, or above 180
feet use the Classic 250.
If the wire size between the DC source and the Classic is larger than the Classic's DC terminal connector
you can use a splicer block or similar connector to reduce down to #4 AWG close to the Classic. The
MidNite E-Panels are supplied with a PV input bus bar that accepts up to 2/0 wire