Posted tagged ‘Servo motor’

How To Understand the Difference Between Servo & Stepper Systems

March 3, 2015

Hi, Adam Ring here and I’d like to talk a little bit about the differences between stepper motors and servo motors. There is a difference in the way they are structured and controlled. Stepper is typically 50 – 100 pole brushless motor where a servo is basically a 4 – 12 pole brushless motor. The stepper typically doesn’t have any kind of encoder for feedback, sometimes you can add it later on as an option where a servo is always built with some sort of feedback device whether it be an encoder or a resolver in order to tell its drive the position of its motor shaft.

Now if we take a look at the speed torque curve for each of these motors they’re very different. A stepper motor has a lot of torque at slower speeds. In fact quite a bit of holding torque because of so many pulls it can have a lot of holding torque at low speed and then the faster that you run, that torque actually starts to drop off. But you look at the speed torque curve of a servo motor it’s actually very, very flat and you get a constant torque regardless of what speed you’re traveling up until its maximum speed.

If we look at the amount of current that a particular motor draws, a stepper motor typically is going to draw full current whether it’s standing still or running. In some cases drives that you use with them may have a feature where you can reduce the current if they sit still for a long enough time, but other than that they are basically just drawing full current all of the time which also produces extra heating, as you can imagine. Servo motors on the other hand use the amount of current that’s required in order to get the motor to hold or move as demanded by the application. So typically they are going to run a lot cooler and they also have a neat little feature that enables them to produce on occasion 2 – 3 times their rated torque for short periods of time as a peak rating.

Let’s look at the cost of installing a stepper or a servo motor. As you can imagine, a stepper motor is typically going to cost less. The motor construction is simpler, you don’t typically have the feedback and the electronics to control the motor are typically simpler and less expensive. With a servo motor obviously they are going to have some type of feedback device built into the motor and then the drives that we use to control them typically are a little more involved when it comes to how they are designed and built and typically costs a little bit more.

A little bit about the application these might be used in: the stepper motor is used in applications requiring about 2000 rpm or less where you need a lot of torque at the low end, whereas a servo motor is typically used for your higher speed applications that are more dynamic and require more acceleration and deceleration typically 2000 rpm and higher.

So depending on whether you’re doing indexing moves with a light load or really dynamic moves with higher loads you can choose whether to use the stepper or the servo motor. Whether you’re in the market to purchase a stepper motor or a servo motor or not really sure which one is the best choice, visit we have an excellent knowledge center where you can come and research differences, catalogs, white papers, videos and learn more. After all we are Innovative-IDM, Home of the Legendary Customer Experience.

Parker MX80L Miniature Stage Series

March 29, 2013

Parker”s MX80L Miniature Stage, the smallest linear servo-motor driven positioner in the industry, is redefining high throughput automation in the world of miniature positioners. The MX80 is a high performance linear servo motor stage designed to meet today”s 24/7 production demands requiring rapid-fire positioning of light loads within a small work envelope.

Parker, MX80L Miniature Stage Series

For more information or to order your Parker MX80L Miniature Stage Series Linear Servo Motor contact Innovative-IDM at 877-906-2100 or send us an email at

Another LEGENDARY Customer Experience

February 26, 2013

We get so many written accolades, sometimes it’s tough to keep up. This one is pretty good, and it was addressed to our president.

From: Shane  <>
Date: February 26, 2013, 9:14:09 AM EST
To: Gene Gray <>
Subject: Thank You


May I first say, the reason for the delay in this letter is I am the eternal pessimist, and I had to see the machine run without failures for a while before writing a letter of kudos. Us, in conjunction with Innovative IDM, just completed a servo upgrade from a competitors servo, and all I can say is WOW. After two consecutive failures on the competitors servo motors, we decided it was time to investigate another supplier, and due to Elliot’s persistent sales presence (nagging), we elected to try Yaskawa.

When the motor arrived, half the size of the competition, we all chuckled and wondered if someone had lost their mind. The installation was a little bumpy but not as bad as expected. Brian Miller showed up with Adam and the fun began. We suffered mechanical failure during commissioning, that was pretty impressive to say the least. (Brian, I hope the counseling for the PTSD is going well). At this point, Brian and Adam were completely honest in their assessment of what happened and did not try to hide that a mistake had occurred. This is THE exception to the rule from what we have experienced in the past and was very refreshing to know it still exists.

The next hiccup was a burnt up brake that happened at 5:30 on a Friday. I called Elliot and told him to get a motor out here because the brake was not holding. Elliot called me back within the hour and asked if someone could receive the motor by noon on Saturday. This was a pleasant surprise due to the competitors response on both failures was a month lead time.

The bugs were worked out methodically, and the line was put into production. This line is now our go to line when we need long runs of good product. All I can say is good job guys, we are not easy to impress, but you guys did the job. Keep up the good work!


Shane, Electrical Supervisor

Discontinuation Notice: Omron W-Series Servo System

July 18, 2012

Omron W-Series Servos R88D-W/R88M-W will be discontinued March 2013.  Recommended replacement is the G5-Series servos R88D-K/R88M-K.  Click here for more information and a list of affected parts and recommended replacements.

Looking to upgrade to the G5-Series servos?  Call Innovative-IDM at 877.906.2100 or email us at