Maximum pension contribution by an Employer via salary sacrifice

Is there a maximum weekly amount my employer is allowed to pay in Salary Sacrifice pension? They are claiming that their maximum is £847 per week and that it is a regulatory maximum. I can not find any rules that state that there is a maximum a company can pay in salary sacrifice for pension. As I understand it there is a cap of £60k per year. Assume an employee wanted the employer to pay £1,000 per week/£52,000 per year of their salary in to pension as a salary sacrifice would that be possible or are there any regulations stopping the employer from doing so?

Hi 

A salary sacrifice arrangement must not reduce an employee’s cash earnings below the National Minimum Wage (NMW) rates.
Employers must put procedures in place to cap salary sacrifice deduction and ensure NMW rates are maintained.
NMW rates are at National Minimum Wage and National Living Wage rates

Thank you