The appeal against the decision of the SANZAR Judicial Officer will take play on Wednesday at 11:00.
It will be a telephonic conference and the panel will be appointed on Tuesday.
Following disciplinary hearings on Monday, lock Bakkies Botha was cleared to face the Crusaders in the Super 14 semi-final at Loftus on Saturday, but Nel was suspended from all rugby for four weeks following his citing for a dangerous tackle on Sharks fullback Stefan Terblanche in Saturday's Super 14 match in Durban.
Nel's suspension is a severe blow to the Bulls - especially in light of the hip injury to ace centre Wynand Olivier, who has been the country's top centre in the Super 14 competition.
The Bulls will only decide later in the week whether Olivier's hip has recovered sufficiently for him to play in the semi-final.