My friend recently asked me to help him with his outside sign, which was ON all of the time. The contractor merely forgot to tie in the circuit to the timer but, while I was tracing out the wiring, I noticed the Electrical Contractor, which installed the wiring in his new store, pulled individual neutrals with each circuit, a good thing! The other thing I noticed was that he decided to tie all of theses neutrals together? I know this is not a good practice for many reasons but I would like to know the code, if there is one that prevents this? I only had the opportunity to check four junction boxes and all were the same. Multiple conductors with individual neutrals tied together, I’m not as concerned with two conductors and two neutrals tied together, even though it might confuse the next electrician who tries to work on the store, the contractor might just say he was doubling the neutral size like so many do for computer heavy applications. I’m concerned he might have done the same for three or more circuits and since the store is a Laundry Mat with a lot of electronics. There might be a chance that when and if someone works on these circuits live, he may damage some of the electronics inside the store. Has Cook County implemented neutral tracers for individual circuits? In the two circuit two neutral scenario should the two neutral wires be identified as one in the panel and or at all junction boxes for safety?

Thanks for your help