Spyder Farmer Automatic Fan control

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Well-Known Member
Nov 12, 2016
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South of the Mason Dixon in Virginia
I contacted technical support because I don't think the controller is working right. Here is their response.

Here are some operation methods.
1.HIGH TEMP: High temperature automatic start mode, if the ambient temperature detected by the sensor exceeds the set temperature, the fan will be started ,

2.LOW TEMP is the low-temperature automatic start mode, which will start the fan if the ambient temperature detected by the sensor is lower than the set temperature.

3.HIGH HUMID: refers to the automatic high humidity startup mode, which will activate the fan if the ambient humidity detected by the sensor exceeds the set humidity.

4.LOW HUMID: refers to the automatic low humidity start mode, which will activate the fan if the ambient humidity detected by the sensor is lower than the set humidity.

I am thinking with low temp and/or low humidity, fan should throttle down. Am I missing something. Might as well turn the fan on to manual and just leave it that way.
It seems their answer for every issue you have in that tent is to turn the fan on. I don’t understand how high and low humidity can both be resolved with a fan being turned on, but what do I know?
I am with you Kevin , low temps for sure should stop the fan

but not sure on the humidity

i can see where some would think low humidity would kick on the fan , stir the air some , it may raise the humidity

we were never concerned about humidity around here , it is always low but I prefer growing cannabis in low humidity any day over high humidity
maybe try a different brand?

compare the two?

automation aint all its cut out to be eh
I would have thought the fan speed would be variable instead of just on/off but the ‘help’ they sent seems to say it just is on/off. I think a grower on here called TDub has a controller that sets the fan speed based on VPD(essentially a theoretical ratio of temp and humidity that helps plants flourish best).
I haven't been too impressed with any of the temperature/humidity controllers available. They are all essentially on/off devices with at best a high and low speed. I ran part of the summer with AC Infinity's controller where below 80 degrees (at night) it dropped to "2" and at 80+ degrees it went up to an extremely loud "9". There is no in between other than a non-controllable 30 second ramp up/down time. I eventually decided to just control the temp and humidity in the outer room with an AC and keep the fan at a reasonably quiet "5" setting.

There are some controllers out now that have separate heating and cooling plugs, so you can run a heater and fan from the same controller. I have one I plan to try this winter once it gets cold enough to actually need heat at times.

Anyway, the Spider Farmer fan controller is exactly the same as AC Infinity's controller. I think they have different fan plugs to make them incompatible, but the analog out is still 0-10V I have read. You set the low speed with the device in manual, then switch to auto and set the high speed and values for high temp, low temp, high humidity and low humidity. I believe it's mostly intended to operate in a single mode with the others set to out of range values.

Here is the AC Infinity manual which seems a little easier to understand than the SF version.

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