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It’s quiet in the café today, with a light drizzle falling outside. While waiting for my second Americano, I thought I’d talk about this Siemens Field PG M6—a machine I have a love-hate relationship with.

Let’s start with the first time I got my hands on it. It was the 6ES7798-0AA "Advanced" model; opening the box revealed a hefty beast with a magnesium alloy casing. It featured a 15.6-inch screen, a metal body, and rubber bumpers on the corners—cool to the touch. Honestly, the build quality was worlds apart from a standard laptop; holding it gave me a reassuring sense that this thing was built to take a beating. It had a die-cast magnesium alloy body, rubber corner bumpers, and even a retractable handle. At the time, I thought: "It’s expensive, sure, but at least it’s solid."

Then the price tag gave me a reality check. This thing cost around 7,000 euros—and that wasn't even the price in Germany. I was stunned. To put 7,000 euros in perspective: you could buy a top-spec MacBook Pro *plus* a high-end gaming laptop, and still have enough left over for a decent monitor. Yet, the PG M6 Advanced came with an i7-8850H (6 cores, up to 4.3GHz), 32GB of DDR4 RAM, and a 2TB SSD. Those specs were decent back in 2018, but if you compared it to consumer-grade laptops at the same price point, its performance got absolutely crushed. Someone on the PLCTalk forum put it bluntly: it’s just a laptop with lackluster performance, wrapped in a plastic shell, stamped with a Siemens logo, and sold for several times the price.

But having said that, why do I still use it?

The I/O ports are a real lifesaver. With a standard laptop, if you want to connect to an S7-300 PLC, you have to dig out a USB-to-RS232 adapter and pray the driver doesn't fail at a critical moment. The PG M6 has RS232, Profibus DP/MPI, Profinet, and a Simatic Memory Card slot built right into the chassis. When you get on-site, you just plug it in—no need to rummage through your toolbox looking for adapters. TIA Portal, STEP 7, and WinCC flexible come pre-installed; you can get to work the moment you turn it on. That "ready-to-go" experience is something a standard laptop simply can't offer.

But the touchpad—honestly, it drives me up the wall.

A guy on the Siemens forum wrote a post titled "TouchPad horror" after using the device for three months; I nearly laughed out loud when I read it because his experience mirrored mine exactly. The touchpad lacks dedicated mouse buttons; when you press down, the system first tries to determine if you're moving the cursor before registering the click. The result? You try to click, and it thinks you're dragging; you try to drag, and it thinks you're clicking. That user said every drag operation felt like preparing for a bungee jump—a description that hits the nail on the head. Even worse, if the work environment is slightly dusty, the touchpad quits working after just ten or fifteen minutes. Wiping it with a dry or wet cloth does nothing; you just have to wait half an hour for it to recover on its own. I keep a wireless mouse in my bag at all times now—I basically pretend the machine doesn't have a touchpad.

The battery is another recurring issue.

I used my own M6 for about a year and a half; the battery health deteriorated rapidly, and eventually, it stopped charging altogether. A quick search on the forums revealed—surprise, surprise—that plenty of others were in the same boat. One user had the battery fail completely after four years; they bought a replacement, but the new one wouldn't charge either. The battery indicator stayed green, whereas the manual states it should be orange while charging. A Polish repair blog noted that this problem is common after 12 to 18 months; many people assume the motherboard is dead, but replacing the battery actually solves the issue—in 90% of cases, you don't need to replace the whole unit. The spare part is the 6ES7798-0AA10-0XA0 (a 10.8V / 8.25Ah Li-ion battery); it’s quoted at £283.50 (excl. tax) in the UK, while in Germany, you can find compatible versions for anywhere from €117 to just over €200. It’s not cheap, but it’s far more cost-effective than replacing the entire machine.

The screen's durability also came as a bit of a surprise.

The magnesium alloy chassis is marketed as shock- and vibration-resistant, yet the screen itself is surprisingly fragile. A user on LinkedIn complained that the screen scratches easily—even slight contact with a hard object leaves a mark, and some have even shattered. While mine hasn't broken yet, there are already two fine scratches on the display, so I have to be careful during daily use. It’s baffling: the chassis is built like a tank, yet the screen is as fragile as fine china.

Let me mention one aspect that made the investment feel worth it.

I was once commissioning a production line at a client's site. An engineer nearby was trying to connect his standard laptop to a PLC but couldn't find the adapter; he was sweating bullets. I pulled out my PG M6, plugged in the RS232 cable, fired up TIA Portal, and got the job done in five minutes. I still remember the look he gave me. In that moment, I truly felt the €7,000 price tag was justified. It came with licenses for legacy software like STEP 7 Professional 2017 and WinCC flexible 2008 pre-installed—no manual setup required. Only those in the industry know just how much hassle that saves.

All in all, my biggest takeaway is that this machine is like a veteran colleague with a terrible temper but rock-solid reliability. The touchpad is awful, the battery is disappointing, the screen is delicate, and the price is absurdly high. Yet, when you’re out in the field and really need it, it never lets you down. With its comprehensive ports, pre-installed software, and rugged build, there’s simply nothing else like it on the market. Whether you buy it depends on whether you’re willing to put up with flaws that *could* have been fixed—but weren't—just for the sake of peace of mind. My coffee’s getting cold, so I’ll wrap this up.

Lithium-ion battery SP306 For Siemens Simatic Field PG M6