You have not provided sufficient information for an intelligent answer.

First, to get a grasp of your knowledge and necessity of the drive split, I suggest you diagram the conveyor chainage vs. lifts and falls and drive locations with nameplate distributions. Not having tonnage, belt speed, vertical and horizontal curves, belt width, counter-weight, idler spacing, et al., leaves a void as to offering some response.

These comments are secondary to assisting without doing your engineering. Mixing 900 and 750 kW is unusual. We do not know how you plan to distribute these or how to control them. We do not know if there are uphill and downhill gradients.

I can say, most likely you will cook the goose (motors) with any soft-starter = voltage regulator, unless you have a large refrigerator.

CST and Inverter or Wound Rotor Motor system can all be made to work, as a general comment. How to do it is a more complex task and not get it wrong.

Having so many drives of different sizes is a puzzle only you can answer. ■

A more important aspect of your request is: Do you know how to model the conveyor using Dynamics Analysis? I do not think you do since you are asking some fundamental questions on starting and stopping = dynamics control, regulation, and "what if" power loss scenarios.

I can only offer a word of the 4 Cautions to the Arab Proverb:

1. I know not and do not know I know not - shun me My Paraphrasing

2. I do not know I know not - awaken me

3. I know I know not - teach me

4. I know I know - follow me ■

2. I do not know I know - awaken me instead of "I do not know I know not" - awaken me ■

Hello,

As per conveyor information, the total installed power is 2 x 900 + 2 x 750 = 3300 kW. So, conveyor seems to be of positive power. If so, the options for multiple drive could be as below:

1) Head end (discharge) pulley primary drive 1/3rd power + Head end secondary drive 1/3rd power + Tail pulley drive 1/3rd power. This means only one type of drive, and conveyor has 33.3 % power at tail end.

2) Head end (discharge) pulley primary drive 2 x 1/4th power + Head end secondary drive 1/4th power + Tail pulley drive 1/4th power. This means only one type of drive, and conveyor has 25 % power at tail end.

3) Drive at intermediate location on carrying run 1/3rd power + Head end (discharge) pulley primary drive 1/3rd power + Tail pulley drive 1/3rd power. This means only one type of drive, and conveyor has 33.3 % power at tail end.

Although above shows only one size of drives in sr. nos. 1, 2 and 3, but it is not compulsory. There can be conveyors with 2 or 3 sizes of drives also. The exact drive arrangement will depend upon conveyor profile and design analysis.

4) Any combination of drive locations and their proportions, as you like.

Then make workable design of belt conveyor for all the options you are considering. The workable design means the conveyor design construction which will ensure guaranteed performance without any hassle, and thus all options are technically at par. Then choose the conveyor drive system which results into most economical installation i.e. considering total of mechanical, electrical, structural, civil work and maintenance operation cost. For making commercially viable (saleable) design, it is advisable to make price estimation for each case, and then make the decision.

If the designer is new to subject, he will take long time, whereas one who is frequently dealing with the subject will be able to pinpoint quickly the most economical (ideal) system.

Regarding type of startup for drive, one finds many such installations using scoop type fluid coupling or VVVFD drive. Discuss with the supplier of these or other startup options and choose the one you like. Possibly economy can result by constant acceleration startup and relatively long starting time. There is no prohibition if one wants to use sharp startup and usual startup time, except that these will result into costlier installation.

Ishwar G. Mulani

Author of Book: Engineering Science And Application Design For Belt Conveyors (new print November, 2012)

Author of Book: Belt Feeder Design And Hopper Bin Silo

Advisor / Consultant for Bulk Material Handling System & Issues.

Pune, India.

Tel.: 0091 (0)20 25871916

Email: conveyor.ishwar.mulani@gmail.com

Website: www.conveyor.ishwarmulani.com ■