Please stop waking him up. It isn't helping him. It is just going to make him more tired and it isn't doing anything to help his bladder develop or his brain to turn off the urine production.
He needs to stay dry at least 2-3 weeks every night before he gets to stop wearing pull ups, unless you don't mind doing a lot more laundry for the next couple of years. I can't afford the extra money it costs to do laundry each and every day. It is at least 2 loads more, times 30 days in the month, that is 60 more loads of laundry per month.
To wash and dry a load of clothes it costs me, utility bill increase, about $1.5 per load. That means the increase of bed linens and jammies would add $45 to the bills, if that does not include water then that would add even more cash being paid out. Then there is the additional laundry detergent and dryer sheets and fabric softener. I use Gain, it is $10 per 45 load box. The bleach is a couple of dollars a gallon, dryer sheets are a $3-$4 per box, fabric softener is also. So add that to a normal month it adds up to
$45 or more for utilites, electricity and natural gas
$10 for water if not paid in rent or lease
$10 for extra laundry soap
$2 for bleach
$4 dryer sheets
$4 fabric softener
So, not using pull ups when someone is not staying dry is very costly, it could add up to $75 a month to your bills plus it takes up your time, which is worth something too.
A box of Huggies overnight pull ups are under $20 at Walmart. Even if you need more that one box, that would still not add up to the higher amount of the added laundry, plus I like having free time to not do laundry.
All the alarms do is make more laundry, every time he sprinkles or dribbles it will go off, making even more laundry. Plus everyone in the home will start having signs of sleep deprivation. It serves no purpose to put anyone through this.
You can search this topic and read the same responses over and over and over again. We all say the same thing over and over again. It takes time, the brain has to tell the kidneys to stop producing urine. The body one day clicks and when the chemicals in the body signify the body is asleep certain things are supposed to happen, we don't act out our dreams because we are somewhat paralyzed, we don't make urine so we sleep all night and do not pee due to a full bladder, it does not matter how much we drink, a dry bladder is less likely to wake us up to go. The body does what it is supposed to whey it is time.
Search in the box for night time dryness, nighttime potty training, etc...you will find all kinds of information.