Dead SSR heatbed wont heat no more
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@dad003 what is the specification of the bed heater?
Make sure that you set the PWM frequency for the bed heater low in the M950 command that sets up the output, for example use Q10 to set it to 10Hz.
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Is it an AC or DC heated bed?
For AC, I use this one: https://www.auberins.com/index.php?main_page=product_info&cPath=2_30&products_id=30
For DC I have this one, but never ended up using it: https://www.auberins.com/index.php?main_page=product_info&cPath=2_30&products_id=288
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A few dumb questions:
- Is the heater LED on the main board flashing or at least lit?
- Have you disconnected the heater and checked continuity/resistance?
- What resistance was measured?
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Sorry for the late response didnt had much time lately and i got this week the new SSR from auber
Swapped out the SSR and all is good now . it was just the cheap SSR that was causing the problem.
Checked the config as well added "Q"parameter at the M950 for the bed heater didnt had it apaprantlyThe high switching speed allows this SSR to be operated in pulse width modulation (PWM) mode up to 2 KHz.
Here the next question which number should be optimal for the "Q" parameter since this SSR can do a pwm of 2KHz ?
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Assuming your bed has significant thermal mass you don't need to worry much about switching speed.
I use Q10 on all my bed heaters which are heating 6mm of aluminum and have seen no reason to change it.
Frederick
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@fcwilt okay thank you
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@dad003
Could have sense cool it down ... also if the peak is higher just at the start of the heating. At least it will not be stressed. Maybe will last much more.
(ex not cooled on 12V 28A 340Watt - SSR 60A DC/DC - placed on a small aluminium bar)
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I solved in a old style way
https://forum.duet3d.com/topic/24785/cooling-ssr -
@giostark it was on a aluminum heatsink , it was never hot either has well when i checked it , it was just a cheap bad quality ssr
