Startup Time For 3MW 8ZL48 DG Set

Have you asked the dealer? Or Sulzer? Emergency standby by gen sets are usually up in a matter of seconds, pehaps a minute on the outside. But that is as much a matter of switch gear as it is gen set startup time.

It is necessary to define the conditions.

The DG set can be loaded with in few 3-4 minutes. Need to clarify following. Are you going to start DG on heavy fuel? (Heavy fuel -what is the type, Is the fuel is heated to achieve proper viscosity.) Is Start-up system is ready to DG start, including electrical system.

It is better to contact the engine manufacturer.One thing is starting an d then loading.Engine manufacturer is the right person to furnish this.

Hay, What is exactly POWER OUTRAGE?

Wangito.

Hi Kvsubramanyam

Starting a standby set of this size is not going to be an easy deal at all in fact it is extremely complex and will definitely need the manufacturers input. Sets of this size are not meant to be used as standby units. Not only do you need to consider the warm up time required by the Prime mover. There is also the effect of apply the load loads of this magnitude cannot be simply bought on line as would say a 200kW standby gen-set. I assume that the system/network is connected to step up and step down transformers. if this is the case then the best method would be to isolate the secondary load from these prior to start up and to start the generator with all the transformer primary's connected. This prevents the main Breaker from tripping which it will do if you attempt to close it against connected transformers the inrush current is to high. The only way I can see it working is as follows. In the event of a primary power failure disconnect all the load from the transformers, close the primary CB for all transformers, start the generator, when the generator is up to speed warmed up and the transformers are fully charged introduce loads in steps until the system is fully operational. When Primary power is restored wait until a convenient time and then shut the system down stage by stage and repeat with the primary system.

I thank every one for putting comments. We have 2000KVA 33KV/ 415V three transformers. Two transformer out puts are paralleled for the sake of equal load sharing. Apart from this we have five Diesel Generating sets of each 1000 KVA to be used during Mains Power failure. We have mains power cut from 4 to 6 hours a day; and some times we face power failure without any information. Our cost per unit (KWH) on Diesel Generating set is Rs. 12/- per unit. Now we have planned to buy one used Heavy Furnace oil based Generator that starts initially High pressure compressed Air then Diesel and then switch over to Furnace oil. We are going to have all required switch gear transformers, etc to step-up 3000 KVA generator out put and directly feed in to our 33KV line. Our sub-station got all the necessary arrangements to distribute power to various loads with good protection. (Double-bus bar System). my basic question is What best (lowest) startup time a can expect from this generator:model- 8ZL 40/48 of Zgode make.

Dear sir

You have asked for the start up time for the set.

What I understand is the time required for the set to start . I think you have also said it should start on compressed air.I think set should start within a minute once starting pulse is given to the air starter

May be you require the loading pattern, once the system starts..This depends on the Alternator and the Engine.

Kindly check for latest pollution norms .In some areas HFO fired dg sets are not allowed in India.Secondly what is the engine make.The warming period for engine is the most critical and this can be obtained only from engine manufacturers.

Dear Sir,

model- 8ZL 40/48 of Zgode Sulzer make. This I have already mentioned. This is old model (1984) engine and hence I may not get correct reply from the supplier. This is the reason that I am contacting CR4 for advice.

If the set is old please check the lub oil circuit.For the set take the load immediately on starting ,you may have to do the following.

1) Pre heat the engine circulating cooling water,for this you should have a heater with thermostat to keep the water at required tempertature(the manual of the engine might have specified.)

2) Pre heat the Lubricating oil as said above.

3) Run the lub oil pump periodically to keep the lub oil pressure at required level( this also should have been specified in the manual.

This means we should always keep the engine in working condition such that the engine can take the load immedietely on starting. As I said earlier starting of the set is not a problem.

Perhaps you might be knowing Kirloskar W8v series slow speed engines, the same system was followed.Many of the textile mills in Tamilnadu and Andhra pradesh had these sets about 25 years back