Bosch RH540M vs RH540S Rotary Hammer Review

If you want to drill, chisel, and demolish concrete, then you might want to get the best tool for doing such task right? Of course, there’s no question that a combination rotary hammer will beat a hammer drill in many aspects. In regard to this, we’ve seen years of debate over whether Spline is much better compared to SDS-Max.

Gladly, the Bosch Company has settled the question. Without further ado, let’s review two of Bosch’s rotary hammers in order to find out the best tool for your needs.

Bosch RH540M vs RH540S Rotary Hammer Review

1. Bosch 1-9/16-Inch SDS-Max Combination Rotary Hammer RH540M

Bosch 1-9/16-Inch SDS-Max Combination Rotary Hammer RH540MThis rotary hammer is absolutely made for professionals and is hands down the fastest and hardest hitting rotary hammer in its category. This beast tool can give 6.1 feet per pounds of impact energy while only weighing in at 15.2 pounds. Moreover, the RH540M gives optimal productivity in all day drilling as well as chiselling applications.

Its 12-amp electric motor offers up to 170 to 340 RPM in rotary mode and 1,200-2,750 BPM in its hammer mode, which will pound through concrete just like nothing. Also, its toll free SDS-max bit system lets you for single-handed, instant bit changes. Aside from that, its Vario-Lock mechanism will also let you position its chisel tip to 12 different working angles, thus making it much more convenient for you. The Bosch RH540M Combo hammer comes with a dual mode selector knob and service minder brushes.

As Bosch discussed in their guide to rotary hammers, SDS-Max and Spline bits come in various sizes.

For instance, SDS-Max bits for the RH540M range from ½ to 1-3/4 inches. On the other hand, the Spline bits are a little bit smaller. However, the SDS-Max system comes with distinct pros such as its one-handed tool-less bit changes and its automatic bit locking.

As for the RH540M Combination Rotary Hammer, it comes with 6.1 foot per pounds of impact energy for demolition throughout the day. And its selector switch makes it much easier to pick between functions. It also comes with three options. The first one is the chiselling, then the drilling, and the Vario-Lock that allow you to place the chisel into twelve varied angles. In addition, it comes with an auxiliary handle for optimal control and extra comfort.

Furthermore, near its two-finger trigger, you will also find its variable speed dial. The RH540M 12 Amp motor has no-load speeds of 170-340 RPM as well as 1500-2900BPM. And although it is a brushed motor, it is made for quick maintenance.

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Also, this hammer drill is very powerful and goes from drilling holes to demolishing concrete effortlessly. Its performance for a midsize hammer drill is exceptional. Of course, an impact energy of 6.1 feet per pounds only means that it can drill faster and hit harder.

Its minimum vibration provides you total control of the tool and allows you to drill holes with optimal accuracy. Its weight takes care of the drilling so you don’t need to put additional pressure. Also, its 12 amp electro motor gives 170-340 RPM in the rotary mode and 1200-2750 RPM in the hammer mode making it one of the best rotary hammer drills to use for masonry or concrete-related works.

Also as it is a very versatile power tool, you don’t need to worry about elaborate controls and settings anymore. Just turn its dual-mode option knob to switch between its three mode which are the hammer only mode, the chiselling mode, and the viz mode, and its Vario-lock function. So no more contorting or stopping over your body into daunting positions to chisel perfectly because the RH540M will do all the positioning for you. In addition, you can pick different speeds for both your chiselling and drilling applications with its variable speed dial.

You don’t also need to worry if your tool is working efficiently because its service minder brushes won’t just make the tool work at optimal capacity, but it will also remind you when a maintenance service is due to get a long-lasting performance.

And lastly, while you power away at tile or block, the RH540M protects itself and the user from too much stress. First, it comes with a soft start and consistent speed under certain load. And then its clutch disengages the transmission if the bit binds, and that halts the tool from twisting from your hands.


  • Its power cord is 8 feet long
  • It is CSA-listedfor safety
  • Comes with auxiliary handle and carry case
  • Operates really fast
  • Its Vario-lock mechanism is huge in terms of being versatile
  • Service minder brushes are absolutely a huge bonus since it will ensure your tool to operate at an optimal capacity
  • Adjustable handle that makes for comfortable operation and extra control
  • Easy drills a hole of up to 4 inches in diameter
  • Comes with built-in integral clutch that disengages in the occurrence that the bit binds up which can ultimately save your wrist
  • Tool-free bit changes with automatic bit locking
  • Dust protection and maximum impact energy transfer rate
  • Best in class impact energy of 6.1 feet per pounds
  • Vario-lock positioning rotates and locks chisel into 12 different positions
  • Combination dual mode selector knob lets the users to select between chiselling mode, hammer drilling mode, and the vario-lock function
  • Variable-speed dial for controlled drilling and chiselling applications
  • Made by a prominent brand
  • Ergonomic handle that distributes the weight for ease of use
  • Comes with option al auxiliary handle in the box
  • Reasonable price
  • Can do large holes
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  • Though there’s enough cord to be used in various situations, it may not be for those individuals who prefer convenience of a cordless hammer
  • Though the power to weight ratio is great, its weight is 14.2 pounds and is quite heavy compared to its competitors
  • It comes with a 120 voltage cord, thus if you’re in a country that uses a higher voltage then it should have a step down transformer in order to reduce its voltage

2. Bosch RH540S 1-9/16-Inch Spline Combination Rotary Hammer

Bosch RH540S 1-9/16-Inch Spline Combination Rotary HammerThe only difference between the RH540M above and the RH540S is their bit system. The RH540S utilizes Spline bits that range from 3/8 to 1-3/8 inches in size. But this rotary hammer also accepts non-Spline bits that come with ¾ inch round hex shanks, which RH540M can’t do.

Similar to the power tool mentioned above, the RH540S can put out 6.1 foot per pounds of impact energy to punch through tile and rock. In addition, it comes with a dual mode selector knob that switches between hammer-drilling and chiselling. Also, it offers the same Vario-Lock feature that allows you to position a chisel at twelve various angles. That’s very convenient in terms of demolishing concrete in tight corners.

It also comes with the option to select one of a variety of speeds from 170-340 RPM and 1500 to 2900 BPM. This lets you match the speed to the material you’re working on. With its protection against bit binding and soft start-ups, this generation of rotary hammer is much safer and more user-friendly.

Moreover, its brushed motor is built for long-lasting life because it has modules for immediate maintenance. It is easy for a technician to replace the power cord and brushes. And the transmission and motor protect against overload too with its automatic clutch disengagement if the bit binds.

And lastly, both of these Bosch rotary hammers allows you to drill holes of up to 4 inches in diameter with a concrete core bit, or up to 2-1/2 inches with a concrete through-hole bit. And their maximum concrete capacity range is ½ to 1-3/8 inches deep.


  • Equipped with variable speed dial for chiselling applications and controlled drilling
  • Comes with varo-lock positioning which locks and rotates chisel into 12 different positions for optimized working angle
  • Combination dual mode selector knob
  • Best in class impact energy for maximum productivity in all day drilling
  • Comes with spline bit system
  • Accommodates all accessories with spline or ¾ inch round hex shanks
  • Comes with a power cord that is 8 feet long
  • CSA-listed for safety
  • Comes with auxiliary handle and carrying case
  • Comes with great warranty offer
  • 360 degrees auxiliary handle which provides a wide range of movement along with operator comfort
  • Comes with integral clutch which disengages torque transmission if the bit gets into a bind situation
  • Grounded design
  • Comes with hard-hitting combo hammer
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  • Quite expensive
  • Tend to produce a lot of vibration but still manageable


Since the capability and power of both Bosch RH540S and RH540M are almost similar, the deciding factor is their bit system.

If you’re already using either SDS-Max or Spline, pick the rotary hammer that matches the bits you’re already using. On the other hand, if this is your first Spline tool or SDS-max, then it might be worth doing a little bit of research in your area to learn what other contractors are currently using and how hard it is hard to acquire one type or the other.

Now, if you’re looking to purchase the best corded hammer drill, you’ll need to sort through the many choices which can make you feeling confused. Some inexpensive options might be tempting you. However, resorting to cheap products might lead you to regret after a couple of use.

Professional remodelers and concrete contractors need not just a powerful tool but also a versatile one that can actually meet all of their drilling and chiselling needs.

And as per recommendation, the RH540M comes from a prominent brand that has more than a century of experience in making quality tools. When you have a tool that ticks all the boxes, there’s no need for you to think twice.