Analog DC load 36V 1A for ebike charger testing - DIY Low cost design

[Kiriakos GR]

I am having one cooperation with a man him selling electric bicycles, when electronics fail I am the man for such repairs.

Usual failing part this is ebike battery charger, after this getting repaired (by me)  I need a way to verify 30 minutes trouble free operation of those chargers.

Today I thought to combine some parts and make an analog DC load for my own workshop.

The concept it is simple,  36~41 DCV them pass thru one 20W ceramic resistor, they downgraded to 18~19V in conjunction with consumption caused by a 24V car lamp.
20W ceramic resistor this is assembled as bread sandwich and locked in aluminum cage for cooling, and also there is active cooling too.
One stabilizer LM78075  (7,5V) this receives input of 18~19V and has output of 7.5V and this is power source for DC fan and active led panel meter ( this working as voltage meter).

When this Analog DC load gets powered up, ebike charger this uses it as load.
Specific ebike chargers they are capable for constant current mode at about 1.7A and therefore consumption of 1A this is a good performance test for them.
Basically when something of those chargers electronics it is wrong or bad, you may expect an quick (small scale)  explosion.     

Ceramic resistor value that I did use, this is my secret and this information is shared only with people supporting by a donation this Blog. 
Aluminum plate this is from old TV set ( High voltage section ).