Temperature drifting

[MHG]

So I love my apex and I have it doing everything. I have learned to ignore the ph probe since it tends to drift off and goes bad about once a year but that is for a different thread.

Yesterday while performing tank maintenance the tank seamed really cold. In the summer it normally feels cold but it was noticable cold so I grabbed an off the shelf thermometer and it looked a couple of degrees older. I took my chiller controller off my frag tank and that one also showed it a couple degrees colder...after taking every thermometer I had in the house they all showed it colder.

So I left my digital one on there and would compare them throughout the day. Particularly when I hear my chiller power up... At 80 degrees I hear it power up. Look at the apex and it is 80 degrees. Before the chiller compressor turns on it is down to 79.8, then Bach up to 80.

Yesterday I got an alarm email from the apex. Temp greater than 84 degrees. But the stats say 78.8. In the same email.....

I don't think it's a power surge as the entire system sits on a $1000 ups.... Do the thermometers go bad?

[aquamanic]

Any probe (or its port) can fail but the temp probes are pretty robust so that wouldn't be my first thought.

Honestly, it sounds like interference. You could have an electrical spike in the probe, it reads 84 for 1 second which trips the email alert. By the time the email process fires up and grabs the outlet and probe states the probe is reading normal again and that's what gets sent out.

Try unplugging the probe, drag out the wire and lay it on the floor around your tank then put the probe back in the water. Run it that way for 24 - 48 hours. See if the problem goes away. Keep the wire away from anything with high amperage or a ballast.

[MHG]

Well could be I guess although it's been there for 2 years and nothing anywhere near it has changed. That temp of 84 never showed up on the graph.?

[aquamanic]

That temp of 84 never showed up on the graph.?

Think about it. I don't know what your logging interval is - let's say it's 10 min. Every 10 min. the controller takes a snapshot of probe values AT THAT MOMENT. In between logging intervals the probe values can be whatever.

Now the controller runs through all the programs once a second or there about. So the email alarm can 'see' a probe value that may never be captured in a log entry. The controller is looking at probe values 600 times and capturing them in the log 1 time in a 10 minute period.

nothing anywhere near it has changed.

But things do change. Wires move as you mess with equipment. Electronics fail completely or components gradually fall out of spec. Hey, it probably isn't interference but it's an easy test and at least you'll know.

[schwaggs]

It could be a bad probe. I have one probe on my system that periodically goes crazy with random high and low readings but when that happens, it is typically caught on the graphs.

Try unplugging and plugging the probe back in several times (to clean the connection) to see if that changes anything.

[MHG]

Well I just reset the system and did the unplugging thing (should have tried that first). Let's see what happens... I was showing the system to a friend yesterday and while we were standing there it was fluctuating about .5 degrees up and down and back again....

[SloppyWhenWet]

I had to send in my apex for 60 bucks I got it fix. My temp would lock hot and turn no heater on or tell me its 18 degrees F and lock them on. the PH would be off as well. Almost cost me my tank. Sucks but things do fail. May have to do delay on any heater or cooling where for 1 min the temp must be there or not. Do this on controlled HVAC other wise toggles too much. Most things have time delays.Weather changes so much in an hour(RH and temp) its unreal.

[MHG]

60 bucks. The temp probe is only 29 bucks...Do you need to send your whole apex in?

[Vinny Kreyling]

Mark,
Try a new probe 1st.
If the problem persists then the unit needs a look at.

[MHG]

I agree. I am also checking with apex on how much and where to buy a second base unit as a backup. My system is so completely automated by this thing that removing it for a failure or a repair would be an ungodly chore.


I so wish they had an advance replacement program.

[MHG]

Well it's not the probe.... Bought a new one yesterday.... Got this alarm today...


Alarm Statement: If Temp > 84.0 Then ON

Jul 06 2013 18:06:19
Temp *pH ***
79.0 8.09


Still waiting on apex to come back on a price for a second base unit to keep as a spare....they opened a ticket on my question..... Must have been the first person to ask for just a base unit...

[SloppyWhenWet]

yeah I had to send in base unit to be repair. Something's was messed up on the board. If you get a RMA, they will issues a back up for 210 or something. This is the apex box with all the connections.

[MHG]

$249 for the base unit....


Anyway they gave me some trouble shooting to try. I just need the time to do it...

[pkarakis]

I gave up on having the Apex control temp. I put a Ranco thermostat on and have it control a plug in heater tube. My temp will stay within one degree constantly. Check out my graph on reeftronics (Pete_K). I currently don't have a chiller since my sump is in my basement, but the unit I got from them supports a chiller as well. Best $100.00 I've spent on my system.