gene cafe roaster CBR-101 Heater box

 

 

besides the 3D rotating drum, This heater box is the core technology of the coffee roaster,

some info on the heater :

part no:

Genecafe 230v Heater Box CRA97-003A

Genecafe 230v Heater Box CRA97-004A ( Australia)

Genecafe 240v Heater Box CRA97-004A

 

 

For roasters manufactured 2016 and earlier. The lead wiring is approximately 16" in length.

For roasters manufactured after 2016. The lead wiring is approximately 6" in length.

 

A01~A06: 

 

the mica shell is only 1mm thin, and easy to break. this is reason why gene is selling the whole box as an item.

the aluminium case has many inner curve surfaces, with radius of 5 mm or more. buy the mica sheets are rectangular and meant to bend to the inner curved surfaces.  there is quite a lot of unusable spaces inside.

nichrome wire

 

for 110V version: 

given 1200W

~0.8mm diameter(meas),

110*110/(2.87 ohm/m)

gives 10.08 ohm and 3800mm long

4200mm ( by rough measure)

est resistance is ~ 2.47 to 2.72 ohm / m

very likely to be 0Ni25Cr20 wire

the surface load is ~ 13.8 w/cm2

 

with wire gross surface area ( 6 + 3 )x 4x2 = ~ 72 cm2, surface load: ~16.6 w / cm2, Cr25Al5 or higher resistivity heating element have to be used

Kanthal

heaterplus

relation with air speed

heating element design 

 

 

bimetal thermostat switch ( thermal protection for safety)  markings:

 

150C,ST-12,SEKI

sekicon

 

as this bimetal switch is located in the air flow path, just before the air is heated up, the choice of 150 deg C setting is understandable. ( same bimetal switch is also used in imex roasters)

It is for safety reason, in case the hot air exit port is blocked, or the blower fan fail, the heater box temperature rise to dangerous level, this switch will be open to stop heater coil from further heating.
 

 

 

From 220V photo estimation:

0.45 diameter wire, ( 0.35 wire? )

8.5mm length per segment

10 loops for 4080 mm it total

9.87 ohm / m ???