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Old 11-04-2016, 11:15 AM
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ChrisV (Chris)
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Join Date: Aug 2015
Location: Sydney
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David

Just depends upon the current they draw. I've used IRF520 MOSFET module. This can do 1amp as is, and up to 5amps with a heatsink. I've used it on a 4" refractor and an 8" SCT and its fine without a heatsink - but conditions don't require a massive heat drive in Sydney. The rule of thumb is that if the mosfet feels too hot then it isn't coping - so add a heatsink or go for a higher power module.

I couldn't find the specs on the Kendrik straps. But the Astrozap 4" heater is 0.6A, 6" is 0.8A and 8" is 1.2A - so it will be fine with those. Just look up whatever heater strap you have and see what current it draws then compare to the above IRF520 specs. And don't forget - most of the time the heater will be running on a low duty cycle if conditions aren't terrible. So if the heater is running 50% duty cycle this equates 0.6A for the above 8" strap.

The thing about the setup I have described is that it uses simple interchangeable modules, so if you need higher power then just get a higher power mosfet module. I'll have a look for some higher power modules when I get a chance. But really, if your need to draw more than 5amps - thats 60W ! Might as well pull out a hair dryer !!!!

Thanks for your interest. Chris

Quote:
Originally Posted by DavidTrap View Post
Hi Chris,

Can dew not or kendrick dew straps be used with this device??

Ta
DT
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