12V AC-AC Wall Transformer, 1A, 2.5mm x 5.5mm Plug | AC-121B
12V AC-AC Linear Wall Transformer, 1000mA (1A)
Part AC-121B is a wall-mount linear AC-to-AC power adapter with 12VAC output at up to 1000mA (1A) and a 2.5mm inner diameter x 5.5mm outer diameter straight barrel plug. It requires a 120VAC, 60Hz power source and is intended for indoor use only.
Important: AC output, not DC. Use only with equipment that specifically requires 12VAC alternating current (~). Confirm the required voltage, current, connector dimensions, and fit before ordering. This non-regulated transformer may measure above 12V with no load.
Technical Specifications
- Part: AC-121B
- Input: 120V AC, 60Hz
- Output: 12V AC at 1000mA (1A) maximum, approximately 12VA
- Connector: 2.5mm inner diameter x 5.5mm outer diameter straight barrel plug
- Type: Wall-mount linear transformer, non-regulated
- Use environment: Indoor use only
Application Requirements
Consider Part AC-121B only when your equipment documentation specifies 12VAC input, requires no more than 1000mA (1A), and accepts the stated barrel connector. Matching these specifications is a starting point, not confirmation of compatibility with a particular device.
Before replacing an existing adapter, compare its label and connector with your equipment requirements. Check connector insertion depth and available clearance for the wall-mounted transformer. Do not select a replacement based on plug appearance alone. No specific device or brand compatibility is claimed.
Frequently Asked Questions
How do I know whether my device needs AC or DC?
Check the device label and documentation. AC is indicated by VAC or the ~ symbol. This transformer supplies 12VAC and must not be used with DC-only equipment.
Is a 2.5mm plug the same as a 2.1mm plug?
No. Those measurements refer to different inner diameters. Part AC-121B uses a 2.5mm inner diameter x 5.5mm outer diameter barrel plug. Confirm both dimensions and connector fit before ordering.
What current requirement can this transformer support?
Its rated output is 12VAC at up to 1000mA (1A). Your equipment must require 12VAC and no more than 1A, with the correct connector and any other manufacturer requirements satisfied.
Why might a voltmeter show more than 12V?
This is a non-regulated linear transformer. Its no-load voltage can measure higher than the rated output. Check your equipment documentation to confirm that a non-regulated AC supply is appropriate.
What should I check before ordering?
Confirm 12VAC output, a current requirement no greater than 1A, the 2.5mm x 5.5mm connector and its fit, a 120VAC 60Hz power source, indoor use, and clearance for a wall-mounted transformer.
