[rygar]

I just switched out all my outdoor lights with new ones. The transformer to the best of my knowledge is 120watt. The 5 lights I attached are only 18watt each. I attached it to the cable running underground and all the lights work.

My only concern is that the transformer is buzzing almost like squeeling when the lights are on. i am not sure whats going.

Can someone give an idea on what i should do or what to look for what to change.

thanks

 

[rygar]

so i did more snooping.
the transformer is rated to handle 150 watts.
i have 5 lights using up 90 watts.

Should i leave it as is?
BUy a new transformer?
Add a dimming coil?
or
Switch to LED bulbs?

 

[bob22]

From Intermatic site instructions for their 121 Watt transformer. I assume these should be comparable to your's: (I added bolding)

Install OUTDOORS ONLY. Use ONLY with 12 volt low voltage outdoor landscape lighting products.
• Add up all bulb wattages for a maximum total of 121 watts.
• Mount power pack at least 10 feet (3 m) from pool or spa.
• Mount power pack vertically at least 12 inches (30 cm) above ground. Do not lay on the ground.
• Plug power pack directly into an outdoor GFCI outlet with a weatherproof cover marked “wet location.”
• Do not use extension cords.
• Do not use in dwelling units.
• When connecting wire at terminals, do not allow insulation to get under the clamping plate, and
firmly tighten the terminal screws.
• Do not mix solid or stranded type wires under one screw.
• Use 16 AWG MINIMUM low voltage outdoor cable.
• Keep a minimum of 10 feet (3 m) of wire between the power pack and the first fixture.
• Do not coil extra cable around the power pack. Leave extra cable at the end away from the power pack

 

[oberkc]

Most of these types of transformers have an audible buzz, from my experience. Assuming your tranformer is nothing more than one of those found at the typical home improvement store, I would be tempted to replace it you believe the buzz is unusually high. If you are staying with incandescent, try another one like it.

I don't believe I would replace lamps with LED without also replacing the transformer type. I would replace it with a regulated power supply to best ensure voltage stays within a prescribed range regardless of load. This is, by the way, the approach I took. My power supplies now are all inside and make no noise that I can hear.

 

[dmxtothemax]

Most transformers make some noise,
But cheap or loose transformers make even more noise,
Is it a good quality transformer ?
Is it secured tightly in its enclosure ?
Is it an electronic switch mode supply ?
Or is it just a transformer ?

 

[Knucklez]

noise is normal for cheapies. the more expensive transformers are vacuum impregnated which is done to solidify the wires so they don't vibrate (and thus wear away the enamel insulation).

Knucklez