It’s pretty simple to understand once you know how! Assuming you’re on the most recent scheme, every year you accrue 1/54th of your salary for that year.
So, say you earn £27,000 in a year, you will accrue a £500 pension.
Say you earn £27,000 every year for four years, and then leave the NHS, you will have accrued £2,000 for those four years.
That £2,000 will be paid to you in retirement every single year. It’s called a ‘defined benefit’ pension and is very valuable, as you accrue guaranteed pension payments for much less money (in terms of your monthly contributions) than if you had a private pension, or a ‘defined contribution’ pension as with the majority of other employers.
So, OP, look at the annual salary for your new job, divide it by 54 and that is what you will accrue every year. The more you earn, the more you accrue!