I have a large transformer (see below) that I wanted to switch on/off from a digital platform using a solid state relay. The equipment works without any issue and makes no noise when the solid state relay is bypassed but the transformer makes a buzzing noise when it is in series with the relay. I tested the equipment with the relay and the noise and it seems to be working but the buzzing noise worries me and I fear for the transformer.
This is my SSR: PF240D25R
My qusetions as follows:
- Why is my transformer making an audible buzzing noise with the SSR, while there is no audible noise without the SSR? Is it caused by the approx 1.6V drop (see the datasheet)?
- How can I stop this noise?
- Is it safe for the transformer or should I stop using this SSR?
UPDATE 1: The control circuit is a Raspberry PI Zero (GPIO: 3.3V) and the resistor is 330R that makes the current 0.01A
UPDATE 2: My SSR is a 'Random Turn-On' type