Digital Aquatics Archon

[n2585722]

There is in a way. One is your input or output and one is a ground. All the grounds are connected inside the IOE.

 

[EuroDriver]

There is in a way. One is your input or output and one is a ground. All the grounds are connected inside the IOE.

How to know which are which? I connected my 0-10v wires, plus wiring for 3 float switches I plan on connecting today, assuming that signal wire first, ground second.
Is there a pinout diagram for the IOE? I couldn't find any info on the DA website or forum

 

[n2585722]

It will not matter on float switches as there is no polarity with the switch itself. If your ramp is working correctly then you must have the outputs correct.

 

[EuroDriver]

Yeah I figured I must have guessed it right. I just concerned that if all the grounds are connected together & I mix up polarities on something down the road, I'm going to throw everything for a loop.
I'm going to hit up DA for a pinout diagram

 

[n2585722]

I will see if I can find one.

 

[pickupman66]

Are you looking for a pinout of the rj45 ports or of the ioe itself?

 

[n2585722]

The push connectors on the IOE.

 

[EuroDriver]

Yes, the push connectors on the IOE itself, thanks.
I believe the Archon user guide gives the pinout schematic for the RJ45 connectors

 

[EuroDriver]

Anyone know if the Archon is capable of reading ORP negative values?
I hooked up a biodenitrator this weekend. I acclimated the ORP probe (via an SL-1) in the sump for a couple days before calibrating it. I finished the calibration pretty late at night and it was reading a very low value (around 60 or so). In the morning, it was up to 160 so I figured it was good to go, stuck it the biodenitrator and at the end of the day, I reduced the output to about 1 drop/second.
This morning, the ORP was reporting a value of about -25 and as of right now, it's reporting -82.
For one, I thought the SL-1 did not have the capability of reporting negative values and I'm also skeptical that the biodenitrator chamber could go anoxic in less than 24 hours.
I'm worried because I ordered the probe online and the wet storage capsule arrived dry - the solution was crystalized. Thus, I don't know if I'm dealing with a bad probe or whether I'm actually getting a true anoxic reading.

 

[pickupman66]

To be honest I am not sure. What I would probably do is calibrate that orp probe to a known positive solution and run it in the tank to make sure that reads as it should. From there I would flip it over into your denitrator chamber.

 

[EuroDriver]

That's exactly what I did. I calibrated it, then I left it in the solution for a a couple of hours. It stayed consistent between 400-401 that's why I figured I was good to go.
From everything I've read though, neither the RKE nor the Archon are programmed to read negative values. Thus, either something is wrong or I'm extremely lucky in finding out this capability. Unfortunately, posting in the DA forums is like talking to the proverbial dead horse (sans the violence)

 

[pickupman66]

Sorry about that. I'll see if I can inquire for you. It may be possible. Just not sure

 

[n2585722]

The only problem is the further away from the calibrated value the higher the error value. I am not sure how accurate the reading is since you calibrated at 400.

 

[EuroDriver]

According to the instructions, the calibration target value is 400. It seems for the most part people care more about the fluctuation more than the actual value but for my purposes, I should be aiming for around -170.
Some threads suggest reversing the wires to achieve reading negative values but I'm getting them out of gate

 

[n2585722]

If you are getting negative numbers then it must be capable of getting them. The only question would be how accurate the numbers are. It would be nice if there were a fluid that has a certain negative ORP number.

 

[EuroDriver]

According to what I have been reading is that getting a negative value indicates a faulty probe or a ground fault issue. Having no way to confirm that, I'm a little worried in light of having received a dry probe

 

[n2585722]

If you still get normal reading in the tank water I would think the probe is OK.

 

[pickupman66]

I just heard from Eric. It turns out the archon is capable of reading negative readings accurately. Eric said he uses his to monitor a sulfur denitrator.

 

[EuroDriver]

I just heard from Eric. It turns out the archon is capable of reading negative readings accurately. Eric said he uses his to monitor a sulfur denitrator.

Awesome, thanks for the info! Yeah I think my probe is working correctly. Today it reads -182. That's exactly what I'm using it on as well - a sulfur denitrator. Negative ORP reading is essential to monitor ideal anoxic conditions for the bacteria to thrive yet avoid creating excess hydrogen sulfide.
Eric should post that spec for the Archon - I bet a lot of people would be interested in knowing this. I'll do my part to share this info

 

[crs751]

This is good information. I just set up a nitrate reduction reactor and have read on other threads that there is a way to control the amount of carbon dosing using the ORP probe.