I am installing 27 Monex credit card readers that are capable of doing 17 different forms of payment as of today and growing. They swipe, stab and do touch and go of virtually every card or wallet out there and consolidate the billing to just one account. The older generation of the competition required 3 different components to do what this guy does in a devise about the size of 2 playing card deck like Hoyle produces. Much of the install has gone well in the wash bays but on the commercial stainless steel vacuum cleaners the units boot get almost ready to go operational then click and start to reboot..the issue is the power . Needs to be 24VAC but nearly all 13 produce 28.3 to 29.5 VAC. I tried a doorbell transformer that is supposed to create 24 VAC but it too creates a little over 28 Of course what they're expecting is that you're going to run along distance of wire and that that thin wire over 50 ft you're going to have a drop and then it will likely be in the range that would work but these are not going more than a foot or two Do I buy 20 to 40 ft of wire and let nature take its course are do they make a buck down voltage regulator for VAC to vac like they do for DC to DC. I took a year of electronic in high school so I only know enough to be dangerous and the price tag on these units leaves me wanting to do it right.Advice?