It is unlikely that it needs an RCD.
if you did need an RCD then because of the possibility of dc current reaching the RCD it should be a type B RCD
(not a type B MCB) (possibly a type A) that is sensitive to dc currents as well as ac current.
As an aside you can get type C RCBOs, though I do not know if you can get an a or B type RCD along with a C type MCB in one package.
if you did need an RCD then because of the possibility of dc current reaching the RCD it should be a type B RCD
(not a type B MCB) (possibly a type A) that is sensitive to dc currents as well as ac current.
As an aside you can get type C RCBOs, though I do not know if you can get an a or B type RCD along with a C type MCB in one package.