Redundancy and fails safes

[symon_say]

Hi

I want to know what redundancy and fail safe programs do you have in your controller, for example.

• I've my UV lamp outlet to turn off in case the pump that feeds it is off
• Set my dosing to turn off in case ph raise.

What other fail safes do you have?

 

[TheHarold]

Hi

I want to know what redundancy and fail safe programs do you have in your controller, for example.

• I've my UV lamp outlet to turn off in case the pump that feeds it is off
• Set my dosing to turn off in case ph raise.

What other fail safes do you have?

What equipment are you using? Is it a newer apex w. eb832, that has individual outlet power monitoring?

I probably have 2 dozen, if not more, assorted failsafes.

For example:

• Turning off lighting if the tank temperature is starting to spike
• Shut off any device if they start to draw an abnormal amount of power (& send notification). This happens with jammed pumps.
• Shut down ATO if the sump level is high
• Shut off skimmer if the return pump is off (Or not drawing sufficient power), to prevent it from overflowing.
• Shut off skimmer if the cup is full (Using a float switch connected to breakout box)
• Shut off return pump if the sump water level gets too low, to prevent it from sucking air.
• Shut off doser if pH gets above a set point

And many more

 

[robbyg]

Agree with the above. Make a list of what you have and then visualize what will happen if it fails or in cases where it is possible simulate a failure and then examine what you have on your control that can stop the damage. The answer is not very true traightforward

 

[jim_fitz]

Playing devils advocate I know
But what happens if your controller fails

My fail safe is to double up where possible
I have 2 return pumps, 2 skimmers etc

 

[symon_say]

What equipment are you using? Is it a newer apex w. eb832, that has individual outlet power monitoring?

I probably have 2 dozen, if not more, assorted failsafes.

For example:

• Turning off lighting if the tank temperature is starting to spike
• Shut off any device if they start to draw an abnormal amount of power (& send notification). This happens with jammed pumps.
• Shut down ATO if the sump level is high
• Shut off skimmer if the return pump is off (Or not drawing sufficient power), to prevent it from overflowing.
• Shut off skimmer if the cup is full (Using a float switch connected to breakout box)
• Shut off return pump if the sump water level gets too low, to prevent it from sucking air.
• Shut off doser if pH gets above a set point

And many more

Thanks, those are the ideas I want to read, I have a few of those, but didn't notice it.

 

[ca1ore]

I tend to prefer monitoring/alerts over actual control/intervention, except where the latter won't adversely affect the tank. For example, I run a bunch of flow sensors on my tank. Most of the time an out-of-bounds reading is a sensor failure rather than any kind of actual 'emergency' so shutting something off would actually create a problem rather than solving one. One exception is my UV. If the flow sensor shows no flow through the UV, it is turned off. Not having the UV for a bit won't impact the tank, but an empty unit might shatter …. and that would be a problem. Another exception are the sensors in my skimmate container. If the internal floats trigger or the water sensor detects water on the floor the skimmer is turned off.

 

[Clownfishy]

My Apex

• Turns off dosing pumps and UV if water leak is detected
• Turns of dosing pumps for alk if pH is above 8.60
• Turns of my lights if temperature reaches 28c
• Turns off my heater if temperature reaches 27c (just in case it is stuck on)
• Turns of auto water change if water level sensor come one e.g. water is too high

 

[Tastee]

I have most of the above configured as well. Here are a few others I have.

High level sump sensor to alert in case the return pump fails (no power monitoring available for us in Australia).
Low level sump sensor to alert in case the gravity fed ATO is blocked.
Backup heater not controlled by Apex in case Apex fails the primary off.
Chiller powered by Apex (but not controlled by apex) and turned off if temp drops too low in case chiller fails on.

Another technique I find useful is to configure a VO for the optical sensor with a short defer and trigger the alarm based on that. This can also alert in the case the optical sensor ‘disappears’ as mine did a while ago needing a reboot of the FMM to bring the sensors back.

 

[ingchr1]

I have the following on my P4:

• Powerbars (x2)
  • Each has a return pump, heater and powerhead.
  • All outlets fail on if communication is lost with the controller, with the exception of the primary heater and ATS light. Those two fail off.
• Heaters (x2)
  • One fully rated (125W primary) and one half rated (50W backup)
  • If the primary heater cannot keep up then the backup heater comes on. The backup is set slightly lower than the primary.
  • The thermostats on the heaters are set higher than the controller and should protect for high temperature controller failure.
  • The outlet for the primary heater is set to fail off and the backup to fail on if communication is lost to the controller. My though is this will still give the tank heat, limit the possibility for overheating due to the lower wattage of the backup heater (should the heaters internal thermostat fail) and give me time to respond to the issue.
  • If temperature goes too low (indicating a potentially failed temperature probe or the probe out of water), then the primary heater socket is turned off. The backup heater socket operates as normal, see bullet above for my thought process on keeping the backup on.

Basically, should my controller fail the tank should still run as if there were no controller at all just with a lower than needed wattage heater.