LCD clock numbers not showing with different voltage?

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Benek

72 posts

Master Geek

#175268 23-Jun-2015 14:12

Didn't know where to post this so I'll try in here.

If you're a parent you might be familiar with a Gro Clock. It's a kids clock to aid sleep that shows if it's night or day. It's got a backlight in orange or blue color and then LCD numbers and other shapes on the clock face.

We're traveling in the states and brought it with us. Plugged it in today and the backlight is working fine but the LCD numbers are very very light as to be almost invisible.

Is there a chance the different voltage would cause the LCD display to do this? Very curious if this is th case or if coincidentally it's broken during travel. Any ideas?

geocom

597 posts

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#1329919 23-Jun-2015 14:26

Yes it could be. Have done a quick search and it looks like there is a transformer and it looks to only be able to work on 240v which means that the voltage coming out will likely be lower as it will not switch given the ac voltage is lower than it expects.

You could check with a multimeter the voltage coming out of it or you could just buy a transformer(Switch Mode Transformers are a safer choice) in the states and plug it in you will need to make sure that you keep the pin polarity and the voltage out and the out pin the same. You should try to keep the current out the same however going higher should not be an issue(Unless it uses the current rating as a limiter).
It may be best if you take in the NZ one with you provided they are helpful you should end up with something much the same as what you have.

Geoff E

geocom

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#1329981 23-Jun-2015 15:25

As for why. The LCD will have a contrast pin that needs to be fed a voltage usually this is done with a trimpot and a resistor(Voltage Divider). With the power in being low this voltage will be lower and as such will show with a lower contrast than your used to.

Geoff E

andrewNZ

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#1330001 23-Jun-2015 15:36

Some devices are multi voltage some aren't.

All electrical devices have a rating plate. This tells you the voltage and frequency it will work with, along with the current it will draw and/or the wattage.

If it doesn't match the voltage or frequency where you are, don't plug it in. You risk damaging the device or worse.

NZ is 230v 50Hz
Us is 110v 60Hz

dolsen

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Lifetime subscriber

#1330041 23-Jun-2015 16:29

What I want to know, will the clock be 20% faster?
Assume it has a DC input so no.

Benek

72 posts

Master Geek

#1330326 24-Jun-2015 05:26

Thanks for replies guys. I guess so many electronics these days are designed for a large range of voltages I just assumed it would be. But I should probably unplug it to avoid any potential damage as it's obvious not designed to work on 110/120v.