Pump Won't Restart .... Use Min Time?

[ca1ore]

..... after a brief power interruption. I recently replaced the main return with 1 1/2" flex PVC. When the power cuts, the back siphon is so strong that until it stops the pump volute is 'forced' to spin backwards and the pump will not restart properly. I have plenty of sump space, so the back siphon is not a volume problem; and I have no plans to use a check valve. So I am thinking about adding a Min Time statement to the pump outlet that will prevent the outlet from coming back on for 5 mins after a power loss. Just cannot seem to wrap my brain around the syntax.

FALLBACK ON
SET ON
MinTime 005:00 Then OFF

Will that do as I require; keep the outlet OFF for 5 mins after power returns and then run the pump 24/7?

[suckerfishdish]

This is what i found on the Neptune site.

The Defer and Min Time statements are both outlet timers.

Defer - will delay or defer an outlet from changing its state for X amount of time.

Min Time - will insure an outlet stays in its current state for a Minimum Amount of Time.

The Defer and Min Time statements are the exception to the rule that program statements are processed in order - it doesn't matter where in your outlet program the Defer or Min Time are, they apply after all program statements are processed.

So when would you use one vs. the other?

Scenario: I've got a float that bounces up and down in my turbulent sump. I want to smooth that out so it's not turning my ATO on/off all the time.
Solution: Add a Defer to your ATO outlet program of a minute. That will eliminate the little bounces and only turn your outlet ON or OFF after it's been in that state for a full minute.

Scenario: I want to make sure my lights stay off for 5 minutes to cool-down in case of a power failure.
Solution: Add a Min Time of 5 minutes to your light outlet. Even if you try to turn them back ON in that time, they'll stay off.

So how are they used? Here's an example of each:

Defer 1:00 Then ON
Translated: Defer the ON state for 1 minute. (OFF would be immediate).

Min Time 5:00 Then OFF
Translated: Minimum Time of 5 minutes in the OFF state. (ON would be immediate)

[jacksonpt]

I believe you want to use the defer statement.

Fallback ON
Set ON
Defer 05:00 then ON

That will effectively delay the ON signal for 5 minutes (or whatever time interval you want to use).

[Breadman03]

If using the "Light" wizard on Fusion, the Hysterisis setting is translated as a Min Time command. For example, here is the code for my fuge light.

Fallback OFF
Set OFF
If Time 00:00 to 10:00 Then ON
If Tmpx10 > 82.0 Then OFF
Min Time 001:00 Then OFF

Hmmm. I've got the wrong temp probe. I better fix that

[tkeracer619]

Ran into this problem before and it ended up damaging pumps. Used a check valve on the intake side of the pump. After a few months and the check valve getting dirty it would leak but still stop enough flow to keep the pump from spinning backwards...

[outy]

Originally Posted by ca1ore

...When the power cuts, the back siphon is so strong that until it stops the pump volute is 'forced' to spin backwards

I have a small hole drilled in my overflow at its highest point, it stops the backflow after a long minute of being shut off.

No need for check valve.

I have to have something in case power shuts off, I don't have the room in my sump like you.

[ca1ore]

That won't help. It's the water contained within the 20' of 1 1/2" hose that's the problem. It's only a problem with a very short power interruption. Anything more than a couple of minutes and the hose drains and the impeller will stop spinning backwards and the pump restarts properly.

[ca1ore]

Originally Posted by tkeracer619

Ran into this problem before and it ended up damaging pumps. Used a check valve on the intake side of the pump. After a few months and the check valve getting dirty it would leak but still stop enough flow to keep the pump from spinning backwards...

I had thought about that, perhaps putting in an oversized swing check to limit friction.

[tkeracer619]

Yeah, that's what I did before and probably what I am going to have to do on my 600. There is so much water flowing down that it can backspin the pump rapidly. It can also mess up brushes...

When I work for AAI we had a large tank split a check valve in half at the molded seem on one of those flapper check valves. Never again unless inside a sump where failure isn't a problem.

We know we shouldn't use them to prevent draining a tank or overflowing a sump but this IME is a great use for them. The flapper style has minimal losses.

[ca1ore]

So, at the risk of revealing to all that I am still an Apex dumba$$ (right there on p. 47 of the manual ).... the proper syntax to do what I want is:

FALLBACK ON
SET ON
If POWER EB832_2 OFF 003 Then OFF

Won't stop the impeller from back spinning, but it will prevent the pump from restarting until 3 minutes after power was restored to the energy bar. At that point even if the power was a quick outage, the back-siphon will have cleared.

[jacksonpt]

Interesting. Looks like the code is slightly different for the newer Apex gear.

[Ted_C]

I had this same exact problem with my Waveline DC 12000's - if you dont let the back-siphon complete - the pumps wont restart correctly (you get a flashing light on the controller). This occurs for power outages and funny enough - when I lose connection to the internet (like a modem reboot) - Neptune still doesn't know why my Apex reboots when my modem reboots.

I have one pump start then the next pump starts 20 seconds later (to allow the overflow to "ease in" to full operation.

Here's how I solved it:
1: create a virtual outlet called PwrOutDelay with the following code:

Set OFF
If Power Apex Off 000 Then ON
Defer 002:00 Then ON

2: the programming of the return pump(s):
Return_4_1

Fallback ON
Set ON
If FeedA 000 Then OFF
If FeedB 000 Then OFF
If FeedC 000 Then OFF
If FeedD 000 Then OFF
If Power Apex Off 002 Then OFF

Return_6_1

Fallback ON
Set ON
If FeedA 000 Then OFF
If FeedB 000 Then OFF
If FeedC 000 Then OFF
If FeedD 000 Then OFF
Defer 000:20 Then ON
If Power Apex Off 002 Then OFF

The code statements (especially for "OFF" commands seems counter-intuitive - but they are correct and work as intended. Even though there is no reference to PwrOutDelay in the programming - I kept it in this example. You might not need the virtual outlet.

For the other outlets that need to wait until normal operation is reached - I programmed based on the return outlets. The skimmer is a good example - since I use a baffle-less sump the water level is dependent on the returns running:

Skimmer:

Fallback OFF
Set ON
If FeedA 000 Then OFF
If FeedB 000 Then OFF
If FeedC 000 Then OFF
If FeedD 000 Then OFF
If Output Return_4_1 = OFF Then OFF
If Output Return_6_1 = OFF Then OFF
Defer 002:00 Then ON

Edit: here;s my thread from neptune where the community and I worked on this together to figure it out: https://forum.neptunesystems.com/sho...using-problems

[ca1ore]

Originally Posted by jacksonpt

Interesting. Looks like the code is slightly different for the newer Apex gear.

It's different only in the sense that the older apex cannot use the EB832 ..... otherwise the same.