There are some great answers here, but I thought I could contribute a bit. At my last job I was a process management engineer when I started. This meant taking measurements and time studies of processes in an effort to improve them. After a short period on the job, I was able to refine and automate the processes so much (mine and the ones I monitored) that I was promoted and moved into a more promising career path within the company.

What I've learned in my work experience:

1. Never make yourself indispensable. Doing so means it is isn't possible to move up or onto something different. If you can automate much of your job, you should.
2. You can almost never have too many people that make things more reliable and lessen maintenance. These people pay for themselves over and over.
3. Automating tedious parts of your job leave you available for more interesting tasks.
4. Automating work saves the company money year over year for a one time expenditure. Obviously, there is a variable return on the investment, but in general, it's better to automate.
5. People that take initiative in solving their work problems are not that common. Most people follow the motions and work within set parameters. These people are easily replaced and add minimal value.

There are some great answers here, but I thought I could contribute a bit. At my last job I was a process management engineer when I started. This meant taking measurements and time studies of processes in an effort to improve them. After a short period on the job, I was able to refine and automate the processes so much (mine and the ones I monitored) that I was promoted and moved into a more promising career path within the company.

What I've learned in my work experience:

1. Never make yourself indispensable. Doing so means it is isn't possible to move up or onto something different. If you can automate much of your job, you should.
2. You can almost never have too many people that make things more reliable and lessen maintenance. These people pay for themselves over and over.
3. Automating tedious parts of your job leave you available for more interesting tasks.
4. Automating work saves the company money year over year for a one time expenditure. Obviously, there is a variable return on the investment, but in general, it's better to automate.
5. People that take initiative in solving their work problems are not that common. Most people follow the motions and work within set parameters. These people are easily replaced and add minimal value.

As far as how to handle this with your manager, do two things and do them well.

1. Be eager and proactive in asking what additional work duties you can take on
2. Do not get idle. If you are not given tasks to replace the ones you automate, find ones that benefit the company and yourself (in that order).