Hello Not all of our UPS' have service tags. Only UPS' manufactured in the last couple of years have service tags. If your UPS has a service tag then it is usually on a pull out tab. The warranty period on a Dell UPS is 3 years from date of purchase or if it is purchased on the same order as a rack it will be warrantied for the same period as the rack, whichever is greater. The purchase date is verified by the order number of the purchase. Rather than providing support with a service tag you will provide them with the order number. Thanks
Good afternoon,  We have a Dell USP 500W for our company server and it appears that one or maybe both of the batteries within it have went out. We are looking to replace them or even see if they might still be under warranty, but the system has no Service tag or Serial number on it. Any help you can shed on finding out if it is still covered is much appreciated. Also if you would place e-mail at instead of this company account that would be much appreciated. 
Dell UPS 500W (H900N)