Choosing an industrial power supply and transformer for a control panel usually starts with one question: what voltage does the control circuit need? Many panels step line voltage down to either 115V or 24V to feed control components and logic. If you already know whether your control bus is 115V or 24V, this decision is simpler than it seems. These two 50VA control transformers are both listed at $44.99, so price alone won't separate them. The real difference is the secondary voltage and the input taps each unit supports. Here's how to choose the one that matches your system.
Quick Verdict
Match the transformer to your load voltage. Pick the Hammond PT50MLI if you need 115V control power and your supply can be 208V, 230V, or 460V. Pick the ACME TA-2-81321 if you need 24V control power and your supply is 208V or 480V. They are not interchangeable on the same control circuit.
At a Glance
| Model | Price | Power | Primary | Secondary | Condition |
|---|---|---|---|---|---|
| Hammond PT50MLI - BULK | $44.99 | 50 VA | 208/230/460V | 115V | Used |
| ACME TA-2-81321 | $44.99 | 50 VA | 208/480V | 24V | New - Open box |
Where Each Transformer Wins
- Hammond PT50MLI - BULK: Best for 115V control circuits. It adds a 230V tap to the 208V and 460V primaries, so it covers a wider range of common line voltages and is the only one of these two that works on a 230V supply.
- ACME TA-2-81321: Best for 24V control circuits. It covers 208V and 480V inputs and delivers a 24V secondary, so a 24V control bus can be powered without an extra step-down stage.
Product Notes
Hammond PT50MLI - BULK Industrial Control Transformer 50VA 208/230/460V to 115V
The Hammond PT50MLI is the direct match for a 115V control bus. The primary taps cover 208V, 230V, and 460V, so it can handle a wider set of incoming line voltages than the ACME. That makes it the more flexible option if your facility uses 230V service. The secondary output is 115V, which suits a panel built around 115V control components. The main trade-off is condition: this listing is for a used unit, so you are buying a transformer that has already been in service rather than a fresh unit. If the load voltage is 115V, the Hammond gets you there directly. If you need 24V, this transformer alone won't get you there.
ACME TA-2-81321 Industrial Control Transformer 50VA 208/480V To 24V
The ACME TA-2-81321 is the straightforward pick when the control circuit runs on 24V. It accepts a 208V or 480V primary and delivers a 24V secondary, making it a clean one-step solution for a 24V panel. This listing is described as New - Open box, which gives it a condition advantage over the used Hammond if both units otherwise fit your application. The limitation is the input range: there is no 230V tap, so a 230V supply won't work with this transformer. If your primary is 208V or 480V and your controls need 24V, the ACME is the more direct choice. For a 115V load, it would not be the right fit.
Final Choice by Use Case
Let the control circuit voltage make the call. If your panel needs 115V and the incoming line can be 208V, 230V, or 460V, choose the Hammond PT50MLI. If your panel needs 24V and the incoming line is 208V or 480V, choose the ACME TA-2-81321. The secondary voltage and primary taps are the deciding factors between these two.
