Wich PLC used a lot in industry who have more reputation?

Most industries in the gulf region use Schneider's Modicon and Siemens S7 series, General Electric RX series is also common but not as much as Schneider or Siemens.

In the gulf region: 1st Modicon, 2nd S7 series, 3rd RX series

For additional information about PLCs: the web-page http://plccompare.com/ can be useful even though some of the information is not accurate!

I hope this answers your question

I know that SIEMENS  PLC is the best, search for sep Sevan and you can see by jour self.

The most widely used in the world are in the following order:

1. Allen Bradley

2. Siemens 

3. Mitsubishi

In Japan and Asia Mitsubishi is widely used. While in rest of the world Allen bradely and siemens have good reputation especially in Europe. 

As per my expertise most the the company preferring below PLC CPU.

1. Simens S7-300 

2. Mitsubishi

3. LSIS(XGK Series) 

4. schineder 

5. Rockwell 

Etc. 

I know SIEMENS have good  PLC 

Siemens and Allen Bradly are the top most used brands in controls systems all over the world. 

More than % of the Market Share by Siemens, Rest Sharing between Allen Bradly, Messung, Mitshubishi, Omron, Bechoff, GE, and so Many Brands

s7400 siemens, good and easy programing with simatic

siemens is the most puplic plc

1. Siemens S7-300/4002. Allen Bradley Controllogix 3. Schneider Triconex

Siemens has the greatest share in the market with a contribution of as much as 30.7% towards the total contribution.