ESO Push/Pull Button Shut Down Pool Pumps

Thread Starter

Learning101

Joined Jan 12, 2022
12
I've researched for hours trying to figure out the control wiring of this circuit. I'm at a loss and I certainly need help.

BACKSTORY
Residential community has a community center with three separate bodies of water---main pool, wading pool, and spa. Sub-panel service is 120/240v. Equipment, for reference, are (4) separate pump motors with (1) emergency shut off switch. Motors identified below:

Main Pool Filter Motor - 2.0 HP, 208-230v, 60Hz 1PH kW, 11.0-10.2 MaxAmps
Wading Pool Filter Motor - 1.5 HP, 208-230V, 60Hz 1PH kW, 9.6-8.8 MaxAmps
Spa Filter Motor - 2.0 HP, 208-230v, 60Hz 1PH kW, 11.0-10.2 MaxAmps
Spa Booster Motor - 3.0 HP, 208-230V, 60Hz 1PH, 14.6-12.7 MaxAmps

SCOPE
Currently, the emergency stop switch (DPST toggle) operates just the main body of water. Community manager would like to have all (4) motors/pumps shut down if the emergency push button is engaged.

SOLUTION

  • Remove existing DPST toggle emergency stop switch.
  • Install a dedicated 15A, 120VAC circuit from the service panel to an ESO push/pull button switch.
  • Normal operations: ESO push button pulled out (closed), energizes NO Relay #1, closes contact, energizes (4) 120V control coils of pool pump power relays to close contacts and motors operate---no audible alarm.
  • Emergency operations: ESO push button pushed in (open), de-energizes the NO Relay #1 to an open state along with the power relay contacts of the (4) pool pump power relays---audible alarm needs to sound.
What I cannot figure out is wiring between Relay #1 and #2 for an audible alarm. Once current is removed from the switched side of the EOS to Relay #1, I cannot come up with a switch to break the 120V to the audible alarm.

I've attached a wiring diagram of how far I've gotten.

For those whom are much smarter than myself, can someone help me out? Give some guidance on how to complete the control wiring?
Line Diagram_Wiring_ESO PushPull Button_Alarm_Relays.jpg
 

Thread Starter

Learning101

Joined Jan 12, 2022
12
As of writing this response: 42 views on this post.

Is it normal in this community to have this many views and to have but just one person respond?
 

linuxranch

Joined Jul 24, 2022
1
This is going at this problem the hard way.

There are circuit breakers called shunt trip breakers. They have a solenoid that trips the breaker mechanically when the epo switch closes the circuit.

They are designed to trip all poles of the circuit in question.

Replacing the sub panel feed breaker with a shunt trip breaker will cut power to the feed for all pumps, simultaneously.

You will need to put a latching relay across the shunt trip circuit if you want an audible alarm when the EPO has been pushed.
 

MisterBill2

Joined Jan 23, 2018
12,704
In most industrial applications, where there are multiple motors that each have a starter, such as is described in this post, things are a bit different.
First, each motor has a a separate start button, because starting all of the motors at once puts a very large transient load on the power feed. Usually each motor has it's own stop button, but not always.
The emergency stop will switch off all of the motors, and none of them will start when the E-Stop is reset. So if the system is set up that way, then the set of contacts on the E-Stop button that close when it is pressed can sound the audible alarm, because resetting the E-Stop button does not start anything. That arrangement is often used for industrial systems, where a machine could harm an operator if it started at the wrong time.
If those "relays" are actual motor starters then they should have another contact for holding the coil powered when a start button is pressed.
So the big expense of this change will be getting four normally open, momentary action, start buttons.
And the maintained position E-stop button will need to have a set of contacts that close when it is pressed, in addition to those that open when it is in the "stop" position.
 

Thread Starter

Learning101

Joined Jan 12, 2022
12
This is going at this problem the hard way.

There are circuit breakers called shunt trip breakers. They have a solenoid that trips the breaker mechanically when the epo switch closes the circuit.

They are designed to trip all poles of the circuit in question.

Replacing the sub panel feed breaker with a shunt trip breaker will cut power to the feed for all pumps, simultaneously.

You will need to put a latching relay across the shunt trip circuit if you want an audible alarm when the EPO has been pushed.
Ahhh...I see where you're going with this.

Currently, all the CBs pertaining to each pump motor are in the main service panel and all are non-GFCI protected. The NEC 680.21(C) & 680.21(D) GFCI Protection I found states the CBs have to be GFCI.

I may be wrong in my assumption, but what you're suggesting is a sub-panel be installed with just the (4) CBs moved into the sub-panel with a shunt trip main. And it's a fantastic idea if my assumption is correct. The problem I see with this solution is the shunt trip main would have to be reset manually in the sub-panel. To reset manually is not possible because the sub-panel is in a community and they keep the main service panel, and would-be sub-panel, under a lock. What I see happening is a kid pushing the button and then nobody knows and somebody would have to come out to open the panel and reset the shunt trip main.

You can take a look at the photos and videos in the link below.


Marbella Community Pool

-Jake
 

MisterBill2

Joined Jan 23, 2018
12,704
The arrangement I suggested in post #7 does not require any changes to the breaker panels nor adding a sub panel. It does require adding start buttons for each motor, which those can be on the enclosure of the motor power relays. And it may require a different emergency stop button. So the materials will cost several hundred dollars less. In addition, the controls for reset can be in an accessible location. Also, they will not be using breakers for motor control, which breaker contacts are not rated for motor starting. Instead it uses circuits the same as have been reliable for manufacturing operations for many years.
 
OP, where are the pool heaters in all this? There should be another interlock between the pumps and heaters, in the existing panel. Just to make sure the E-stop, stopping the pumps does not cause heaters to over temp.
Also, the E-stop button likely to be in the pool area so there should be electrical requirements for shock hazard.
 

MisterBill2

Joined Jan 23, 2018
12,704
OP, where are the pool heaters in all this? There should be another interlock between the pumps and heaters, in the existing panel. Just to make sure the E-stop, stopping the pumps does not cause heaters to over temp.
Also, the E-stop button likely to be in the pool area so there should be electrical requirements for shock hazard.
The location is Arizona, A WARMER section of the country. hey do sometimes use pool coolers so that the water does not get too hot.
 

LowQCab

Joined Nov 6, 2012
2,342
I'm trying to figure-out why any of these Pumps need an Emergency-Kill-Button.
They should all be on GFCI-Circuit-Breakers,
and have special attention paid to a stout, redundant, Grounding-System,
both of which are mandated by the NEC ( National-Electrical-Code ) in any case,
and this combination has been proven to be quite safe for at least ~30 years.

What kind of protection is the Kill-Button expected to provide ?

As for ~40+ views, there are plenty of lurkers in these Forums that never Post,
plus all of the moderators will all check out any new Posts, but may not respond themselves.
.
.
.
 

MisterBill2

Joined Jan 23, 2018
12,704
I'm trying to figure-out why any of these Pumps need an Emergency-Kill-Button.
They should all be on GFCI-Circuit-Breakers,
and have special attention paid to a stout, redundant, Grounding-System,
both of which are mandated by the NEC ( National-Electrical-Code ) in any case,
and this combination has been proven to be quite safe for at least ~30 years.

What kind of protection is the Kill-Button expected to provide ?

As for ~40+ views, there are plenty of lurkers in these Forums that never Post,
plus all of the moderators will all check out any new Posts, but may not respond themselves.
.
.
.
Things getting stuck in filter loop suction ports is an actual hazard, and plumbing coming apart is another one.
Normally filter systems are in secured locations. There are reasons enough for wanting an E-Stop function, and besides that there is the CYA requirement for every organization with assets.
GFCI breakers for pumps in a protected area will be subject to nuisance tripping, I would not recommend them. Besides that, servicing is done with the power off.
 

LowQCab

Joined Nov 6, 2012
2,342
All Pool-Pumps are required to be on a GFCI-Circuit-Breaker according to the NEC.
Not complying with the NEC is a sure-fire way to loose a Law-Suit.

The NEC does not make any recommendations for a remote Kill-Button,
but does specify that the means of disconnect
is UL-Approved, "within-sight", and readily accessible at all times.
.
.
.
 
I'm not sure if Arizona heats or cools their pools - my point is OP shouldn't switch off the pumps without the heat/cool system knowing about it. I think the E-stop should effectively assert the STOP button on the control panels.
Although the pump motors are 208/230VAC it's common to use a lower voltage for the control logic. A 120VAC control transformer or 24VDC power. This would not be on the GFIC and needs to be confirmed before wiring that to an E-stop circuit.

It would be best and safest to see pictures of the control panels or wiring diagrams. There could be simple motor START/STOP logic or it could be tied into water level sensors etc. and any temperature controls.

A friend's hot tub party, a woman got her bun cheek stuck on the suction port and by time I ran to shut off the pumps, she had a big hickie. It was funny but not for her, and I guess dangerous if she was under water or it happened to a child.
 

LowQCab

Joined Nov 6, 2012
2,342
"" stuck on the suction port ""

Was this some sort of "home-made" Hot-Tub ?

Commercial Hot Tubs are required by Code to have
a large grill over the Drain to avoid this exact scenario,
( and to keep foreign objects out of the plumbing ).

I've seen absolutely zero Hot-Tub-Intakes that weren't
covered by a plastic grill at least ~8" square, and sometimes as much as ~12" square,
and they're on the bottom, and centered, this is standard practice
In some larger installations, 2 or more Intakes are used,
so that if one becomes blocked it doesn't create very much additional suction at all.
.
.
.
 
I can't remember the exact size (it was not my girlfriend) but see them advertised at 3-6" for spas. I see waterway suction covers have new requirements and improved the design (not flat) to prevent that kind of happening.

But it is a good point to bring up - pool suction drain injuries/deaths happen and the (tragic) Virginia Graeme Baker Pool and Spa Safety Act 2008 changed many requirements, drain covers included:
"There is an annual average of 283 drowning deaths (2003-2005) and 2,700 emergency room-treated submersion injuries (2005-2007) involving children younger than 5 in pools and spas. In addition, from 1997-2007, there were 74 reported incidents associated with suction entrapment, including 9 deaths and 63 injuries."
"The National Electrical Code (NEC) regulation number 680.41 has a requirement for an emergency stop switch for the pump to be located within 5 feet of a public spa in case of bather entrapment."
I see NEC 680.41 is missing specifying any GFCI protection or voltage limit requirement for the E-stop and its wiring. I will write them and bring forward my concern. It's located close (5ft) to the pool. The alarm can be far away from poolside.
Obviously it should be included in the GFCI detection, or be a low voltage, grounded power subsystem. Safety standards agree that under 50V is not an electrocution hazard, which would make a 24V system with grounded secondary safe. Perhaps the community can confirm what I am saying.

OP, you could use one E-stop relay per pump motor, and those relays all supplied by the E-stop button loop. It might be easier using separate relays if each pump has a complicated controller and panel. A single E-stop relay could be used as well but the wiring is a bit more complicated. Let us know what you prefer- I can't tell what your existing motor controls look like.
I am uncomfortable running 120/208V out to the E-stop at pool side without its own dedicated GFCI, or going low voltage.
 

MisterBill2

Joined Jan 23, 2018
12,704
Thanks ti P J M for posting the hazard data.
Now I really wonder about where anybody will find a GFCI for a 3 HP pump motor.
So my suggestions change a bit: Keep the pumps where they presently are, along with the pump control motor starters.
Do all of the button connections using some 24 volt AC relays and 24 volt logic. The wires will be safer and cheaper, and simpler to install. The individual start push-buttons could be on the motor control cabinets, where ever those are located.
Adding individual start buttons is probably one of the upgrades that would be required anyway.
One other thing is that if it is for a municipal government favored project there may not be any permit required, and hence no demands for unreasonable updates.
 
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The engineering rule is "you touch it, it's yours" meaning working on a panel or system, doing changes, additions etc. - it now has to meet modern electrical codes. If not, you are the person responsible for any happenings. Kids in a wading pool is plenty of worry.

OP, you do need to upgrade the electrical to meet NEC Article 680 and get a permit for the work, and understand the scope of work goes beyond adding the E-stop buttons. The E-stop requirement goes back to 2008 so this facility is old and under the radar.
If the facility/community manager refuses, then outright turn down the job and walk away. Having no GFCI's on the pool pump motors means it's a neglected or antique facility or there is an attitude of being too cheap, for decades.
 

MisterBill2

Joined Jan 23, 2018
12,704
I am still wondering about a GFCI for the three HP motor. If the whole assembly is in a closed area without access, and the entire system is grounded, the what?? And do they actually demand those in factories??
Or just for the filter pump right next to the pool???
 
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