24 Volts Bed Heater Problem
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@dc42 Thanks. I did the re-wiring and made a change to the config.g (the F2 fan was set to be controlled thermostatically, I removed it). All of the fans work as they should now. Thanks again everybody.
I'll now have to wait pateintly for the new bed heater. I hope my 350 w power supply will be enough. I am trying to make the calculations using the Wiki page:
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The bed will be 200 Watts
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The hotend is 50 Watts (I also have 40 Watts if I need to decrease the power usage)
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I have 5 steppers. 2 Of them are Pololu steppers with threaded rods. They are 2.8 Volts, 1.7 A, so 4.8 Watts per motor. The extruder is 2.5 Volts, 1.2 A (3 Watts). The Y axis motor is 3.4 Volts, 1.7 A (5.8 Watts), The X axis is 2.8 Volts, 1.7 A (4.8 Watts). In total the steppers require 23-24 Watts. The wiki advises to add 50% to that number, so that's 36 Watts.
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I have 2 blower fans (one 24 V, one 12V (soon to be replaced),, 1 hot end fan and one 8 cm fan for cooling Duet. The 8 cm fan is 12 Volts, 0.18 A (2.2 Watts), The 12 v blower is 0.09A (1.08 Watts), the 24 V blower is 0.06 A (1.44 Watts) and the 24 V Hotend fan is 0.08 A (1.92 Watts). In total, the fans require 6.65 Watts.
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I have a 7 Inch Panel Due (3.5 Watts according to Wiki)
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Duet itself 2 Watts according to Wiki.
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BLTouch, not entirely sure but the web site talks about 5 Volts and a current of 15 mA to 300 mA (peak), so assuming the peak current, it should be around 1.5 Watts
That's my current configuration and in toal it is 299.65 Watts. I assume the 350 Watts power supply is adequate for this purpose.
Also, I plan on changing the part cooling fans with an air pump (the berd-air pump) in the future. The web site mentions the 24 Volts pump's rated current is 1200 mA, but then in the next line it mentions Current rating: 150 ma @ 24 v, so I can't really calculate the power requirement: ıs it 24x1.2A =28.8 Watts or 24x0.15=3.6 Watts? If it is the first, the 350 Watts power supply may be at it limits, if it is the second, then it isn't a problem. (the web site is https://the-makerhive.myshopify.com/products/berd-air-max?variant=33133668499591)
Edit: On AliExpress, there is a similar pump which talks about 12 Watts, so maybe that's the correct number and there may be a possibility to run it with the 350 Watts PSU
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Sounds like you are getting a handle on things. By any chance do the 2 12V fans you have run at the same time? If they do, maybe just run them is series on 24V.
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@joel said in 24 Volts Bed Heater Problem:
series on 24V
Fans aren't perfect resistive loads. So running them in series with PWM won't really work the same way as ganging up two heaters. It's a good way to let the blue smoke out though.
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@joel The 2 12 V fans don't run at the same time. One is for cooling the Duet board (always on), one is a part cooling blower (PWM fan), so probably cannot be run in series.
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Shhh, don't tell my fans that
