MCBXFA5 - does it make sense to test to higher current?

Wednesday 7 Oct 2026, 09:00 → 10:00 Europe/Zurich

Main parameters (2D computations):

Inom	1593	A
Bp at Inom	3	T
Mid-plane stress at Inom	84	MPa
I/Iss (1.9 K)	0.42
Iss (1.9 K)	3793	A
I/Iss (4.5 K)	0.58
Iss (4.5 K)	2747	A

 

Going above 2 kA needs to be carefully verified, 2 kA is about 70 % of short sample...so not so interesing (paramters simple scaling, CIEMAT to provide the good numbers)

I, A	2000	2500
I/Iss (4.5 K)	73	91
Mid plane stress	132	207
Bp, T	3.8	4.7

 

Other limitations to keep in mind:

• Max Vdump = 500 V (above that we are taking a bit of risk, for 2.5 kA current this is 0.2 mOhms (nominal is 0.15 mOhms), according to Franco no problem
• SM18 uses the 2 kA power convertor, but Franco does not see any particular problem on using the big power convertor, they use it with other small magnets operating at 2-3 kA

 

For second season of the discussion

• CIEMAT to verify load line, including 3 D effects
• Asses if 2.5 kA can be considered a safe current or we are taking any risk. We don't want any risk!

 

Susana

 

Update 28/10/2026

• 84 % at 4.5 K of Iss with 2000 ID, 1428 OD; it has the torque of the short verion int he maximum of the parameter space
• 90 % at 4.5 K of Iss with 2500 ID, 0 OD
• a priori, in a short magnet, they tested to around 80 % if Iss at 4.5 K.
• this is the assume Jsc at 4.5 K

• MCBXFBP2 was tested at 4.5 K, with 1590 A (ID)/1431 A (OD), 

1 MCBXFA5 - does it make sense to test to higher current?

Speaker: Fernando Toral (CIEMAT - Centro de Investigaciones Energéticas Medioambientales y Tec. (ES))

MCBXFBP2c, test results (including 4.5 K)