AC4 duty contactors for winch duty in marine environment 4

[edison123]

These AC4 contactors are for winches working in off-shore oil rigs with saline air.

Is there a special spec for marine environment contactors? Or do they come under standard specs?

Who are the reputed manufacturers of such winch duty AC4 contactors?

Thanks for your tips.

Muthu

http://www.edison.co.in

 

[RRaghunath]

Off-shore Marine duty involves vibration and shocks during stormy weather.
There are stringent tests to ensure the contactors meet the subject conditions on off-shore platforms.
Make sure you buy the right contactor.

 

[ScottyUK]

Given the hammering which winches and crane hoists tend to receive, I'd be looking at something like ABB's R-Line bar and shaft contactors. It's an old-fashioned looking design but they're simple and tolerant of severe switching duty.

 

[edison123]

Thanks raghunath. I was wondering if any standards are applicable for marine duty.

Thanks scotty. I did search in vain for such a ABB contactor. Do you have any links?

Muthu

http://www.edison.co.in

 

[ScottyUK]

Hi Muthu,

https://library.e.abb.com/public/167f410be254e1d4c12579c30056d8f8/1SBC104118B0201.pdf

https://library.e.abb.com/public/fe48886c7168bc33c1256deb0042724e/BarMounted_Data.pdf

Schneider's TeSys B range is similar although they seem to have dropped some of the smaller ones from the range:

https://www.schneider-electric.co.uk/en/product-range/667-tesys-b/

Mersen have a decent range:

https://ep-jp.mersen.com/fileadmin/...n-Low-Voltage-Modular-Power-Bar-Contactor.pdf

I'm not sure about Lenoir - I seem to recognise some of the part codes but not the company. From the codes I have a feeling they may have bought the Unelec contactor division in which case they'll be good:

https://www.lenoir-elec.com/en/products/switches/contactors/

 

[edison123]

Thanks Scotty. Both Schneider and Lenoir seem promising.

Muthu

http://www.edison.co.in

 

[che12345]

Dear Mr edison123

Info: These AC4 contactors are for winches working in off-shore oil rigs with saline air.
Q1. Is there a special spec for marine environment contactors? Or do they come under standard specs?
A1. a) In IEC world , your installation is classified under "electrical installations in ships" The relevant standards are IEC 60092-xxx series. See IEC 60092-101 for "general environmental conditions" and IEC 60092-302 for "LV switchgear and controlgear assemblies". As mentioned in IEC 60092, the requirements are supplement and or addition to IEC 61439-xx series.
b) FYI: National marine classification societies e.g. BV, DNV, GL, LRA and ABS etc., publish their own "Rules" and requirements. They also carry out testing and issue certification of materials that complied with their "Rules".

Q2. Who are the reputed manufacturers of such winch duty AC4 contactors?
A2. a) Most reputable contactor manufacturers including ABB produce "modern" contactors that are certified/approved by major classification societies. AC4 duty is always within their standard production programme.
Observation : the [obsoleted] "bar contactor" may not? be certified by some classification societies.
b) it is [desirable] to select the contactor manufacturer that is approved by the classification society of which the off-shore oil rig is being classed.

Che Kuan Yau (Singapore)

 

[edison123]

Thanks, Che Kuan Yau. I will contact ABB India.

Muthu

http://www.edison.co.in

 

[che12345]

Dear Mr edison123

Please sing it out if you have difficulties with ABB India. I had been working in ASEA and later in ABB for the past half a century.
PYI: Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Che Kuan Yau (Singapore)

 

[ScottyUK]

Hi Muthu,

I knew there was something about the Lenoir range that looked familiar - they did indeed acquire Unelec in 1991, and Lenoir were in turn bought by Mersen in 2006.

Looks like it's Mersen you should be talking to.

 

[edison123]

An update. I have got the quotes from Schneider and Mitsubishi for AC4 duty contactors.

Mr Che Kuan Yau - ABB dealer is trying to sell me a derated higher AC3 duty contactor for AC4 duty. Can a AC3 duty contactor be derated like that for AC4?

Muthu

http://www.edison.co.in

 

[itsmoked]

If you look at contactor sheets you see contactor X has AC1 and, say, AC3 ratings down columns depending on voltages. The AC3 column has smaller ratings. Say 20A AC1 and 12A AC3.

The next larger contactor may have the same AC1 ratings as the next contactor down does for its AC3 rating.

What I'm saying is one contactor's AC3 rating is often a larger contactor's AC1 rating.

If you look at a contactor's AC3 rating and find a larger contactor with an AC1 rating that is as large as or larger than the contactor you're replacing it will perform as well as the lesser contactor's AC3.

Things to watch out for are;
1) If the next larger contactor changes frame sizes and suddenly you have space problems in an existing enclosure.

2) Check the coil draw current. If a larger contactor has a higher VA demand for its coil your existing control circuit could have problems. If the controls are line voltage controls this is almost never a problem. If the coils are DC it could likely be a problem. If there is a control transformer for say 24Vac controls it could have a problem or not at all.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[edison123]

Keith - AC4 duty is a different beast with inching and plugging multiple times, which is a severe thermal and mechanical stress raiser. My question is, is an AC3 duty contactor, however much it is derated, fit for severe AC4 duty?

Muthu

http://www.edison.co.in

 

[ScottyUK]

Muthu,

Yes, most of the big-brand AC-3 block contactors do have an AC-4 rating but it's not always easy to find. Siemens, ABB, Schneider all have it tucked away somewhere.

 

[ScottyUK]

Not sure if this will help, it's for the ABB range:

http://www.abbcontrol.fr/Appl-AC3-4/reglette_ac34.asp?lang=2

 

[che12345]

Dear Mr edison123

Q Mr Che Kuan Yau - ABB dealer is trying to sell me a derated higher AC3 duty contactor for AC4 duty. Can a AC3 duty contactor be derated like that for AC4?
A. Most contactor manufacturer's [simplified] catalogues publish the AC3 rating which is the most frequently used. However, almost [all] AC3 contactors in the market can be de-rated/re-rated to AC4, see below.
FYI 1. Reference IEC 60947-4-1 for more information on utilization Categories, determine the current making and breaking conditions related to the characteristics of the loads to be controlled by the contactor, including the testing conditions and methods etc.
2. In brief: category AC4 the Ic=6Ie , and other plugging/inching conditions etc.
where Ic=the current to be broken by the contactor,
Ie=the rated operational current normally drawn by the load.
Calculate the estimated number of operation cycles N' etc are documented in the detailed catalogues.
3. As an example: when operating on the same voltage basis, the [same contactor] rated for
AC3 with breaking Ic=300A, when used under AC4 is de-rated to Ic=180A approx, with the [same] 1 million operating cycles. Alternatively, the same contactor under AC4 operation is re-rated to Ic=700A with 0.1 million of operating cycles.
Note 1. that the current increases but a huge drop from [1.0 to 0.1 million] operating cycles.
2. for "winches working in off-shore oil rigs" may need [less/more] than a million operating cycles, depending on the application.

Che Kuan Yau (Singapore)

 

[edison123]

Thanks Scotty for that hidden nugget of a tool. Wish it gave me a AC4 KW rating straight way instead making me do all the work.

Thanks Mr Che Kuan Yau for confirming AC3 contactors can be derated for AC4 but with a much reduced current and operating cycles.

In my case, the motor is rated 480 V, 60 Hz, 100 A, 8 pole (900 RPM).

Going my Scotty's ABB link, ABB's A210 contactor, which gives me for AC4 duty, 600 A breaking current, 600/6 = 100 A operating current and 100,000 cycles, is needed?

Muthu

http://www.edison.co.in

 

[che12345]

Dear Mr edison123

Info: In my case, the motor is rated 480 V, 60 Hz, 100 A, 8 pole (900 RPM).
Q1. Going my (by) Scotty's ABB link, ABB's A210 contactor, which gives me for AC4 duty, 600 A breaking current, 600/6 = 100 A operating current and 100,000 cycles, is needed?
A1. Reference ABB publication 1SBC100122C0202
AC4 440V<Ue<-690 V ambient temperatur <- 55C
a) Ic=6x100A=600A with 0.1 million = 100,000 operating cycles AC4: ABB contactor A300.
b) Ic=6x100A=600A with ABB contactor A210 AC4: 0.06 million = 60,000 operating cycles.
Note: Promoting, selling, recruiting, coursework and thesis posting is forbidden

Che Kuan Yau (Singapore)

 

[edison123]

Mr Che
Thank you. I will go with A300 then.

I don't think we are violating any ET policies here. It is all genuine questions about a product.

Muthu

http://www.edison.co.in

 

[che12345]

Dear Mr edison123

" I will go with A300 then."
1. I would strongly recommend you to request your local ABB India to refer to their publication Contactors Motor Protection Accessories 1SBC100122C0202 page 2/85 where the data were taken from. This is to reconfirm by your local ABB India to ensure that there is no slip in the proposed selection based on 0.1 million operating cycles.
2. FYI: The proposed contactor is certified by CSA, UL (listed), CCC and approval by BV, GL, LRS, DNV, RINa and MRS.

Che Kuan Yau (Singapore)