When you're wiring an industrial panel, the first question isn't which box to buy-it's what voltage your devices need. Both of these units belong in the industrial power-supplies transformers world, but they work on different sides of the power chain. One steps down line voltage to 115V AC for control circuitry; the other produces low-voltage DC for door access hardware. The two also differ by $32.30 in listed price, with the transformer at $44.99 and the DC supply at $12.69. That gap matters less than matching the output to the load.
Quick verdict
Match the output to the load. The Hammond serves AC control circuits; the 12V 3A supply serves DC lock hardware. Once you know which voltage your equipment needs, the right pick is clear.
Comparison table
| Product | Listed Price | Condition | Output / Rating | Best fit |
|---|---|---|---|---|
| Hammond PT50MLI - BULK Industrial Control Transformer 50VA 208/230/460V to 115V | $44.99 | Used | 115V AC secondary, 50VA, 208/230/460V primary | 115V AC control circuits |
| 12V 3A Power Supply Control for Door Access Control Access Control Power Supply | $12.69 | New | 12V DC, 3A, 30W, AC 110-240V input | 12V DC door access hardware |
Where Hammond PT50MLI wins
The Hammond is the pick when your control design calls for stepped-down AC voltage at 115V. It handles line inputs from 208/230/460V and delivers a 50VA supply for control circuits. It is the only one of the two that can do this.
Where 12V 3A access-control supply wins
The 12V supply wins when the load is DC-powered door hardware. It is new, includes an adjustable lock-release delay, and is designed specifically for access-control wiring. For 12V DC installations, it is the more direct fit.
Product notes
Hammond PT50MLI - BULK Industrial Control Transformer 50VA 208/230/460V to 115V
The Hammond PT50MLI is a 50VA industrial control transformer rated for a 208/230/460V primary and a 115V secondary. It is listed in used condition, so prior service history is unknown. The strength of this unit is its ability to accept different primary voltages and deliver a common 115V AC output for control circuitry. That makes it a practical fit when your panel runs on 208V, 230V, or 460V and you need to power 115V loads. It cannot, however, output DC, so it is not a solution for electromagnetic locks or access controllers that require 12V DC. Its limitation is the used status; if you prefer brand-new components, this may not be the right one.
12V 3A Power Supply Control for Door Access Control Access Control Power Supply
The 12V 3A access-control power supply is sold new and purpose-built for door access hardware. It takes AC 110-240V input and produces a 12V DC output at 3A (30W). The adjustable 0-15s delay lets you set how long an electric or electromagnetic lock stays released, and the NO/NC wiring port gives you flexible hookup options. The pluggable green terminal block and metal housing are practical for panel mounting. The main limitation: it is strictly a low-voltage DC supply. It cannot generate the 115V AC that a control transformer provides, so it will not substitute in an AC control circuit. If your situation is a 12V lock installation, though, this is a direct match at a lower listed price.
Final choice by use case
If your circuit is a 115V AC control bus fed from a 208/230/460V line, the Hammond PT50MLI is the choice and the used condition is the tradeoff. If your hardware wants 12V DC and you need a new supply with an adjustable delay, the 12V 3A access-control unit fits. The $32.30 price gap should be decided after you know your output voltage.
