NEW 600W L.V.TRANSFORMER DOES NOT PRODUCE ENOUGH...

Question

I HAD AN OLD 600W LOW VOLTAGE TRANSFORMER WHICH STOPPED WORKING AND WAS MADE BY H.B. REPLACED WITH A NEW ONE MADE BY H.B. I EXPECTED THAT IT SHOULD GIVE ME THE SAME POWER OUT BUT IT DOES NOT. IT SEEMS MY ELECTRICIAN DOES NOT KNOW WHAT THE PROBLEM IS. PLEASE ADVISE WHAT YOU THINK THE PROBLEM MIGHT BE. THERE HAS BEEN NO CHANGES IN THE NUMBER OF LIGHTS OR THE WATTAGE OF MY SYSTEM