Sequence of events (chillers/cooling Tower)

[dec1220]

Hello,
Circuit breaker for the cooling tower trips, then the chiller goes into alarm mode and both shut off.

I have 2 chillers and 2 cooling towers, they have VFD one set run uninhibited
and the other is on auto mode. Once a week they alternate.


Could the sequence of operation for the chiller and cooling tower affect the breaker?

Thank you .

[HvAckid82]

The circuit break trips because you are overloading the breaker and your chiller needs that tower running to cool the condenser water. I take it you are not a service tech? Call a service company. Where do you work someone on this site could be close by. Some really good guys on here

[kirkH]

It must be the controls to blame because breakers don't trip for a reason.

[HvAckid82]

Get posts up and apply for pro no DIY.

[GA FRANK]

Sounds like you have a vfd problem ,power section, capacitors maybe.
I don't care for vfds on cooling towers. I prefer two speed. I don't care for
towers with drive shafts either.

[dec1220]

The circuit break trips because you are overloading the breaker and your chiller needs that tower running to cool the condenser water. I take it you are not a service tech? Call a service company. Where do you work someone on this site could be close by. Some really good guys on here
No the cooling towers has an indivual breakers and the chillers has the same thanks

[dec1220]

Sounds like you have a vfd problem ,power section, capacitors maybe.
I don't care for vfds on cooling towers. I prefer two speed. I don't care for
towers with drive shafts either.

Well if not for the vfd your cooling tower motor would burn out also process of elimination

[ascj]

Well if not for the vfd your cooling tower motor would burn out also process of elimination


No the cooling towers has an indivual breakers and the chillers has the same thanks

With these statements...your either pulling our legs or you really need to have a experienced mechanic come out and take a look.

[dec1220]

It must be the controls to blame because breakers don't trip for a reason.

i agree with you on that could be a glitch

[HvAckid82]

wtf why would controls make the breaker trip. April fools came early?

[GT Jets]

Sounds like you have a vfd problem ,power section, capacitors maybe.
I don't care for vfds on cooling towers. I prefer two speed. I don't care for
towers with drive shafts either.


Seriously????

I put VFD's on ANYTHING I can modulate....Period. Those who don't agree have no clue why this should be standard equipment an all cooling towers...

As for the OP, this is service call territory all the way, VFD's have a lot of potential energy that can hurt you five ways....Not to be taken lightly.

Be safe and good hunting.

GT

[dec1220]

No the cooling towers has an indivual breakers and the chillers has the same thanks
i am going to swap breakers and see i can not imagine i got a amp reading it look good how ever it would take me few minutes to swap breakers we shall see

[GT Jets]

i am going to swap breakers and see i can not imagine i got a amp reading it look good how ever it would take me few minutes to swap breakers we shall see


Set the amp clamp to data log and wait......IMHO it is not the breaker.

How about a loose connection? :anyone:

GT

[dec1220]

wtf why would controls make the breaker trip. April fools came early?
controls is controled by what the program in tells if one dont agree with the other then guess what happens when a program tell the chiller and pumps and cooling tower all in not in order well you can have evaporator water flow loss or compressor surge these thing and more can happen

[GT Jets]

controls is controled by what the program in tells if one dont agree with the other then guess what happens when a program tell the chiller and pumps and cooling tower all in not in order well you can have evaporator water flow loss or compressor surge these thing and more can happen


OK......I'll bite. What does that have to do with a breaker?:Faint:

GT

[HvAckid82]

What about all of the safety controls that would shut down the chiller in the event that the tower shuts down? WTF is the model and serial of the unit. Call a PRO!!

[dec1220]

Set the amp clamp to data log and wait......IMHO it is not the breaker.

How about a loose connection? :anyone:

GT that is a easy solution property is three year old you would think that may happen in the early stages? the wires dont look burn crisp or loose

[GA FRANK]

Maybe he has a shunt-trip breaker and somthing in controls is tripping it.
Wow this is getting weird.

[GT Jets]

that is a easy solution property is three year old you would think that may happen in the early stages? the wires dont look burn crisp or loose


At the same time though....Wire connections at the bus bars on the breaker, wires to the breaker, wires at the drive etc. etc.

GT

[HvAckid82]

which breaker has tripped? The breaker for the fan motors which feeds the drive then the fan motors?

[dec1220]

OK......I'll bite. What does that have to do with a breaker?:Faint:

GT ok simple vfd we take it for granted before any of your major componets go out your vfd will shoot for you cuircuit breakers it is the easiest fix that when you have to look at other areas .food for your though chillerplant has a sequence when they start up if one does not start in the order that it soppose to then you trip a curcuit breaker (can run a car with out gas their is an order

[manny238]

Sounds like you have a vfd problem ,power section, capacitors maybe.
I don't care for vfds on cooling towers. I prefer two speed. I don't care for
towers with drive shafts either.

GA FRANK
why dont you care for vfds on cooling towers? Every cooling tower should have a vfd IMO.

[ascj]

Not to be mean...but you came here to ask if the controls could trip a breaker. So it was stated, it's pretty much unlikely. So then you go and state it has to be the breaker.

Have you fully checked all voltages, amperages, and connections? You don't look for burnt wires........burnt wires are the result of improper voltages, amperages, or poor connections.

Are you comfortable with the liability of messing with the system? It seems your drawing at straws. You haven't given any concrete info other than a breaker is tripping on a system that probably is worth your job.:couch:

[dec1220]

which breaker has tripped? The breaker for the fan motors which feeds the drive then the fan motors?

yes and i open the vfd which has a memory recorded when it goes out also the fan motor i check inside has well is bus fuses that i check thanks

[HvAckid82]

dec, give us some serious info. Does it trip on start up, what kind of drive and so on. All info for all equipment in question. Your vfd is controlling chiller water temp correct? What kind of chiller and so on and so on

[GT Jets]

ok simple vfd we take it for granted before any of your major componets go out your vfd will shoot for you cuircuit breakers it is the easiest fix that when you have to look at other areas .food for your though chillerplant has a sequence when they start up if one does not start in the order that it soppose to then you trip a curcuit breaker (can run a car with out gas their is an order


The chiller plant goes down because the pump did not start, not because a breaker tripped...A control sequence should not have anything to do with a breaker no matter what.

I think if you slow down, you will go much faster :LOL:

GT

[dec1220]

At the end what we have here is a cooling tower + VFD + curcuit breakers it is not the motor becouse the vfd would have indicated and it did not.IT not motor becouse it is not hot bearing are ok took an amp reading for agruement i increse the vfd speed up the fan and see if it would have take the breaker it did not.....the reason for this breaker to trip is segeunce of operation alternating something is not turn on in order, i have check the breaker and amp it and it okk, NOW my ocd tells me simple swap the breakers and see I still feel that this is sequence of operation

[ascj]

At the end what we have here is a cooling tower + VFD + curcuit breakers it is not the motor becouse the vfd would have indicated and it did not.IT not motor becouse it is not hot bearing are ok took an amp reading for agruement i increse the vfd speed up the fan and see if it would have take the breaker it did not.....the reason for this breaker to trip is segeunce of operation alternating something is not turn on in order, i have check the breaker and amp it and it okk, NOW my ocd tells me simple swap the breakers and see I still feel that this is sequence of operation

So trust you OCD and get back to us.

Here's a question.....what sequence of operation(control wise) will trip a tower fan? Please don't say, it's OCD. Because OCD would have taken all the amperages and voltages. OCD would have also listed the man, model, and serial number of everything that we're talking about.

[dec1220]

The chiller plant goes down because the pump did not start, not because a breaker tripped...A control sequence should not have anything to do with a breaker no matter what.

I think if you slow down, you will go much faster :LOL:

GT ok what happens when you have something in your troat? when a chiller or pump or any thing runs forcefully what do you think happens you pull enough voltage that it may trip and if it did not well then you have a fire

[dec1220]

So trust you OCD and get back to us.

Here's a question.....what sequence of operation(control wise) will trip a tower fan? Please don't say, it's OCD. Because OCD would have taken all the amperages and voltages. OCD would have also listed the man, model, and serial number of everything that we're talking about.

i will get back to you on that the vfd is a danfoss my chiller is earthwise trane 450 centri my cool tower is evapro thanks

[GA FRANK]

O.K. here goes Manny, first off unless your control system shuts down motor completly,
whenever tower is not needed it is going to run at about 30% .This is not enough speed
to keep gearbox lubed properly IMO. Also about every five years the vfd has to have power capacitors replaced,if you do not do this youself it is a pretty suststantial
expense. With two speed control a tower might go for several months without starting
at all.

[GT Jets]

ok what happens when you have something in your troat? ????when a chiller or pump or any thing runs forcefully what do you think happens you pull enough voltage that it may trip and if it did not well then you have a fire

First off, if the whatever is pulling "voltage" I don't think anything bad will happen...:anyone:

Second, what the heck does "runs forcefully" mean?

A circuit breaker in most cases can trip two different ways. Instantaneous trip on high amps (typically about 50 times what the nameplate amperage states, but varies with type) and amp draw, which is either based on temperature or magnetic force.

I don't know what you meant earlier by VFD's take out breakers, you be seeing something I haven't.

GT

[GT Jets]

O.K. here goes Manny, first off unless your control system shuts down motor completly, whenever tower is not needed it is going to run at about 30% .This is not enough speed to keep gearbox lubed properly IMO.

A person would be ignorant if he/she programmed a tower fan FVD to not shut down on some sort of start stop, I personally have never seen such an oversight.


Also about every five years the vfd has to have power capacitors replaced,if you do not do this youself it is a pretty suststantial
expense. Never heard of that either, most of the VFD's built in the last 15 years have non replaceable capacitors.

With two speed control a tower might go for several months without starting
at all.

Same holds true for a VFD....Except multiply that by the fact that it "Could" go all year without going full speed. Saving major energy and wear and tear on all components, the gearbox statement is also false, as long as the manufacturers minimum sped is achieved, they will run virtually forever...I recently changed out two 1975 Marley gearbox towers that had drives on them since 1989 and both had the original gearboxes, the motors had been replaced, but several years ago...

Not trying to fling poo, just keeping it real and hate misinformation....

The installation of a VFD on a cooling tower has many benefits.

In short. Easier on equipment with a smooth low impact start and stop.

Better control of the condenser water temperature making the chiller more efficient.

Saves electrical energy with every revolution of the fan motor.

Less impact on the water treatment because of better control of the air flow which in many cases brings less debris, dust and dirt into the basin...(proven time and time again)....

I guess what I am trying to say is, the benefits out way the drawbacks 10:1, they pay for themselves almost immediately.

GT

[emcontrols]

Wow!!!! Interesting conversations.

A breaker is only good for 80% of its rated stamp at normal conditions.

What is the nameplate volts, phase and RLA for the cooling tower motor? What is the actual amps at say 50hz.

What is the model and serial of VFD (Need to know HP range and voltage etc..)

What is the amp rating on the breaker in question, and is the breaker in question only serving the tower fan VFD and motor and no other loads?

Must have this info to start. Unless you dont want to solve problem.

[GA FRANK]

How can a guy from georgia argue with a guy from california, I do agree with
you about marley towers , have seen the thing same from these towers with two speed control . Chillers need head pressure control.

[GT Jets]

Wow!!!! Interesting conversations.

A breaker is only good for 80% of its rated stamp at normal conditions.

What is the nameplate volts, phase and RLA for the cooling tower motor? What is the actual amps at say 50hz.

What is the model and serial of VFD (Need to know HP range and voltage etc..)

What is the amp rating on the breaker in question, and is the breaker in question only serving the tower fan VFD and motor and no other loads?

Must have this info to start. Unless you dont want to solve problem.

See what I mean? Misinformation.

Where did the 80% load on a breaker come from.

When load tested, they test at 135% of rated amps for two hours. (Speaking about UL 489 rated breakers only).

BTW, most of the information you asked for is not needed for a diagnosis.

What would be more important is, what speed is the breaker tripping on the VFD?.

How is the Drive programmed to meet the overload requirements?.

How far away (what proximity) is the VFD from the breaker in question and also how far away is the motor from said drive?

What steps have been taken to solve the issue (time delays, start up speed, current limiting set points etc...)?

Does this drive have a bypass? Does it work? Does the drive start the motor when reset?

We don't have enough information to slap ourselves with.:spitball:

GT

[emcontrols]

See what I mean? Misinformation.

Where did the 80% load on a breaker come from.

When load tested, they test at 135% of rated amps for two hours. (Speaking about UL 489 rated breakers only).

BTW, most of the information you asked for is not needed for a diagnosis.

What would be more important is, what speed is the breaker tripping on the VFD?.

How is the Drive programmed to meet the overload requirements?.

How far away (what proximity) is the VFD from the breaker in question and also how far away is the motor from said drive?

What steps have been taken to solve the issue (time delays, start up speed, current limiting set points etc...)?

Does this drive have a bypass? Does it work? Does the drive start the motor when reset?

We don't have enough information to slap ourselves with.:spitball:

GT

My bad, what I meant was if you have a 90 amp load on a 100 amp breaker your pushing the limit for normal operation. The breaker could be weak??? I wasnt refering to max inrush on a breaker.

I was leaning towards properly sized and for all we know his sump heater and the bathroom light are wire nuted to it, for that matter it may be a main service panel breaker tripping versus the motor breaker????.

As far as the VFD it should have been set up with all the parameters to shutdown way before the breaker ever tripped. My line of questioning was to see if the VFD is even sized properly or not?

[GT Jets]

Chillers need head pressure control.

Which is exactly my point, two speed towers can only offer three stages of cooling from the sump causing a wave in the supply water temperature to the condenser of the chiller, this causes highly sophisticated electronically controlled chillers to "hunt" with the EXV/Vanes and such to acclimate to the fluctuations, making them less effective and less efficient, it's not much, but noticeable, especially when talking about 10-15 chillers running simultaneously. This would be much less noticeable on older equipment with less sophisticated controls and metering, but still a valid point, just harder to prove.

Don't let my being from California change anything, mechanical stuff is mechanical stuff. :LOL:

Looking to learn and teach, not belittle and criticize.

Disclaimer; I did have a couple of Gold margaritas with dinner tonight, so may be in rare form being ten foot tall and bulletproof and all...:bsing:

GT

[GT Jets]

My bad, what I meant was if you have a 90 amp load on a 100 amp breaker your pushing the limit for normal operation. The breaker could be weak??? I wasnt refering to max inrush on a breaker.

I was leaning towards properly sized and for all we know his sump heater and the bathroom light are wire nuted to it, for that matter it may be a main service panel breaker tripping versus the motor breaker????.

As far as the VFD it should have been set up with all the parameters to shutdown way before the breaker ever tripped. My line of questioning was to see if the VFD is even sized properly or not?


All valid points, we don't see sump heaters around here (it was 76*F here today :D)

But at the same time, I think (too lazy to go back and read it) he said this was a three year old facility, so probably would be OK there....

VFD's cause bizarre stuff to happen when a component begins to let go. It could very well just be a rectifier failing, which if caught in time is a replaceable component on most drives I know of that are only three years old. If not changed early enough will kill other components rendering the drive unrepairable from a value standpoint (these things are getting stupid cheap).

GT