Question about Blade nodes

I am using Fast-v7 and the WP1.5MW model.
The blade.dat file has NBlInpSt=21.
But the .fsm file says blade-node is 1-15.
If I want to change the blade node to 21, how should I set it?

Also, I would like to output Spn1MLxb4, but I get the following error.
How do I set up the output?
It is set at NBlGages=9,BldGagNd=1,2,3,4,5

error↓
Spn1MLxb4 is not an available output channel.

Dear @Kazuya.Nishiyama,

Regarding the difference between NBlInpSt and BldNodes in ElastoDyn, see my post dated Jul 2, 2024 in the following forum topic: Blade crack modeling in NREL 5-MW baseline wind turbine, modifying EdgeStff.

Regarding the blade gauge node outputs, the output name should be Spn4MLxb1 for the reaction loads at output node 4 of blade 1 (you have the “1” and “4” swapped).

Best regards,

Dear Jason.

Thank you for your response.
Problem solved.