Soleniod Voltage Help

I have a VM-010 Change Machine which can be seen on Ebay. I have a new project that requires removing the solenoid and replace with a relay. The Relay that I am using is an G6RL-1-ASI, which can be found at digikey. The first problem that I had was not being able to get an accurate voltage reading on then solenoid input with a standard volt meter. The readings were all over the place and some time, but not all the times in the negatives. I tested this input with several meters with no success. I did a little research on the solenoid and found that these types are normally 12v or 24v. The bill acceptor in the machine is 12 volt. So I went with the 12 volt relay. Now here is the really interesting part, the relay works. However there is a noticeable vibrating sound that comes from the relay at the time of trigger. I have played with these relays before and normally you only hear a click when activated. The output of the relay goes to the Piface input of a raspberry pi. As long as its only one input the piface will pick it up, however if there are consecutive inputs, say 5 in 3 seconds. The piface can not pick it up, however if I press the button manually 5 times in 3 seconds there is no problem. My question is, do you think there is either something wrong with the relay or I have the wrong voltage or the inputs on the piface just cant pick it up that fast?

Have you checked the power supply for the change machine. It sounds like it is producing a lot of AC as well as its 12 VDC.
Frank

chuckey said:

Have you checked the power supply for the change machine. It sounds like it is producing a lot of AC as well as its 12 VDC.
Frank

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yes it plugs into a standard 110 outlet.

The solenoid may be operated by 12VAC. Did you set your voltmeter to AC voltage range ?

yes, I tried everything. All readings were out of control, however I am somewhat of a novice.

When digital multimeter shows weird behaviour (reason may be strong EMI or spike/dips in measuring signal etc.) I use moving coil analog multimeter (an ordinary sanwa YX-360TR) and can achieve understandable result. You may try with such analog multimeter to get voltage reading.

As you said relay vibrates, so I guess you are getting AC voltage. A bridge rectifier converts AC or DC into DC. So use a bridge rectifier to convert the voltage into DC voltage and apply it on relay coil. This should stop vibration.

Perhaps relay vibration is the reason that the raspberry pi is not working properly. But using proper "contact debounce circuit" you may solve the problem though relay vibrates.

" yes it plugs into a standard 110 outlet. ", no that is not an answer. The answer should be something like its 12.8V DC or its 16.9 VAC. . .
Frank

I have asked lots of vendors about the voltage and have had several different answers. One guy said 110 volt, then the next said 12V. I have tested with the volt meter in both AC and DC. All readings are nothing that can be made sense of. I would like to post a video so you can see it. Maybe that will help. I cant imagine its 110 V but I could be wrong, it happens a lot.