Why won't my compressor start?

If the blue arc is coming from the motor it might be an older motor that uses brushes. If the motor is serviceable you would need to take apart the motor and change the brushes. Blue arcs don't usually come from shorts

sounds like the motor is seized, disconnect power then open the rear cover and use a wrench to free the motor. If the motor spins freely you may have a faulty motor starting capacitor

There is an unloader valve and a check valve on the discharge side of the pump. The check valve is not holding and the unloader is not dumping the pressure so the compressor cannot start. Since it is new, you may want to take it back. If not you are going to be replacing parts.

If your compressor is oil-less type, most likely pressure is leaking past piston ring. To verify, remove cover to expose bottom of cylinder (unplug compressor and let out all air). With flashlight, examine the upper-most part of the cylinder (turn motor by hand till piston is at top of stroke). If top of cylinder is scratched, then pressure is leaking past.
For many years now, stores are in a race to have more HP and PSI to attract customers. Customer is really the loser because components used to make the units can not handle the higher pressure. Normally small 115v compressors are set to cut out at 125psi and larger two stage units will cut out at 160psi. Small compressor set to 200psi makes for short lived compressor. Could be compared to driving your car at 100mph all day every day. Longest life is attained when unit is being used at about 60 to 75 % of capacity.
To allow your compressor to reach cutout pressure and keep working for a while, lower cutout to 120psi (pressure switch may be adjustable). To restore to 200psi, replace cylinder/ ring.
If your compressor is oil type, suspect leaking reed valves.

if its just humming and not starting you may have a motor start capacitor on the motor thats bad and can't supply the starting voltage against the compressor

my ace air compressor which is 26 gallon 5 hp will not get over 60psi what is wrong with it please?

your motor overheated from too low a voltage if theres a manual reset try this,also replace the two motor start and run capacitors on the motor body

Yes,but if the max is 125 you don't want to increase it above 110 and set off the pressure relief valve.

YES IT MAY BE THE CAPACITOR . IT COULD ALSO BE THE WIREING IN THE MTR, THE PUNP ITSELF.