Rittal FAQ: 5 Key Locks, Cable Entry, TopTherm, and the Spec Checks I Never Skip

If you've ever had to sign off on a Rittal enclosure order, you know the questions start early: Which series? Which lock? What is that old drawing referencing? I review enclosure specs before they reach customers—roughly 200+ unique orders a year—and this is the FAQ I send to my team and suppliers. Not the brochure version. The stuff I actually check.

• 1. What does Rittal actually make? (A quick company overview)
• 2. What is the Rittal 5 key?
• 3. Why are Rittal cable entry systems so easy to mess up?
• 4. What is Rittal TopTherm?
• 5. TS 8 or VX 25—which should I spec?
• 6. What does "N93" mean on old drawings?
• 7. What one quality check saves the most money?

1. What does Rittal actually make? (A quick company overview)

The short version: Rittal builds the physical backbone of industrial electrical and IT infrastructure—enclosures, control cabinets, climate control, power distribution, and data center racks. That's the company overview in one sentence. Behind the brand is a German manufacturer that started in 1961 and is part of the Friedhelm Loh Group, headquartered in Haiger, Germany.

Most engineers already know the product lines: the TS 8 and VX 25 enclosure systems, the AE and CM wall-mounted ranges, TopTherm cooling, cable entry components, RiLine and Ri4Power busbar systems, and the racks that go into data centers. What I care about is that it's all designed as one system. The lock, the cable entry, the climate control, and the frame all affect each other's performance. When I compared door alignment on enclosures from two production runs last year, they matched almost exactly. That consistency is the thing I actually rely on when I approve an order for shipment. It also means the spares and add-ons I spec today should still match a cabinet purchased next year.

2. What is the Rittal 5 key?

The Rittal 5 key is the flat double-bit key that ships with a lot of Rittal cabinet locks. It's the one that kinda disappears in a toolbox and turns out to open half the panels in your plant. The "5" refers to the key code—there's a range of profiles—but the 5 is by far the most common one on standard enclosure locks.

My honest take: the 5 key is a convenience feature, not a security feature. That's perfectly fine for a locked electrical room. But I've seen project specs ask for the "Rittal 5 key" when they actually needed cylinder locks or keyed-alike control. Those are not the same thing. On one order, we got ten cabinets with mixed lock types, and the electrician ended up carrying three separate keys. Nothing failed—it was just a preventable hassle. Decide the access level upfront. The lock insert is cheap to change before the cabinet is wired, not after. And if you're managing a site with multiple vendors, the 5 key is a handy common denominator—just do not treat it as a security boundary.

3. Why are Rittal cable entry systems so easy to mess up?

Rittal cable entry systems come in a few forms: cut-out cable entry plates, brush cable entries for bundled or pre-terminated cables, and conventional screw-in glands. There are also shielded versions for EMC-sensitive applications. The goal is simple—bring cables in without destroying the enclosure rating.

And that's where I see the gap between intention and reality. The IP code on the nameplate (per IEC 60529) does not survive a hole saw. I tested two identical cabinets side by side once. One used a proper cable entry plate with strain relief; the other had a rubber grommet and a can of spray foam. The first held its IP54 rating in our test. The second couldn't keep dust off the busbar. Same enclosure, similar component cost, completely different result. If you've ever inherited a cabinet that was "finished" by whoever had the sharpest knife, you know the frustration. Match the cable entry method to the rating you plan to claim—before you cut anything. And when a manufacturer publishes cable entry ratings, read the fine print: most assume the plate is installed correctly and the right gland size is used for each cable.

4. What is Rittal TopTherm?

TopTherm is Rittal's enclosure climate control family—filter fans and cooling units that mount onto the cabinet. The newer Blue e+ versions are more energy-efficient and use lower-GWP refrigerant. But the brand name isn't what keeps electronics alive; the sizing is.

The biggest mistake I see is sizing by gut feel. People pick a bigger TopTherm unit because the room is warm or the cabinet looks packed. Oversizing can cause short cycling and, in humid environments, condensation. A unit that's too small is worse: it runs constantly, and the compressor ages fast. I've seen a condensate drip situation over a controller that came down to nothing but a bad sizing decision. The correct approach is 10 minutes of calculation—component heat load, ambient temperature, enclosure surface area, target internal temperature. Rittal's selection software handles it, if you feed it real numbers. And remember, a cooling unit is a maintenance item. Filters, drains, fans—pick a quarterly check and stick to it. If your cabinet sits in a dusty shop, the filter mat is the first thing to starve of airflow; check it before blaming the compressor.

5. TS 8 or VX 25—which should I spec?

Honestly, new projects I review tend to go VX 25, and for a good reason: the 25 mm pitch pattern on the frame makes internal layouts more flexible, and accessories land where you want them. TS 8 is still a proven system, and if your plant already stocks TS 8 accessories, staying there often makes more sense than switching everything for one project.

To be fair, both accept the same system components—lock inserts, cable entry, TopTherm units, bayable hardware. So the decision comes down to existing infrastructure and internal mounting needs. What I don't want to see is a new line mixing TS 8 and VX 25 without a real reason. It complicates spares, racking accessories, and documentation for zero operational benefit. That's a consistency issue, not a brand preference. Check what's already in your facility before you fall in love with the newer catalog page. And when in doubt, ask the supplier for the pitch-pattern drawing before you commit to a frame lineup.

6. What does "N93" mean on old drawings?

I get this one a lot. N93 shows up on older panel schedules, asset tags, and maintenance handover documents. In four years of reviewing specs, I have not found N93 as a current Rittal product family in the catalog. More often than not, it's a legacy code—a drawing shorthand, a customer asset number, or a plant-specific tag that stuck to the equipment.

So when a drawing says N93, here's my rule: don't order from the label. Verify the nameplate, measure the depth, check the lock style and the cable entry pattern. If it's an older cabinet, the modern replacement is usually a TS 8 or VX 25 with better sealing and more accessory options. I have seen a $22,000 redo happen because somebody ordered a "replacement N93" from memory and got a unit that didn't fit. Check the physical unit first. N93 isn't a mystery—it's an incomplete clue. Every legacy cabinet in the plant deserves a fresh label with the actual model, size, and access level. Future-you will be grateful.

7. What one quality check saves the most money?

Write down the environmental specification before you choose anything. Not "indoor use"—actual numbers: ambient temperature range, relative humidity, dust or washdown exposure, vibration, sunlight, and the target ingress protection code. When I implemented that verification protocol in 2022, we made it a rule that no enclosure, cooling unit, or cable entry component gets ordered without the environmental spec signed off on the project sheet.

It sounds bureaucratic. I do not enjoy the paperwork any more than you do. But here's the thing: the enclosure series, the lock, the cable entry solution, and the TopTherm unit all follow from those numbers. Define them first and the rest of the order fills itself in. Our rejected first deliveries dropped by 34% the following year. To be fair, some of that came from better suppliers. A good chunk came from stopping the guessing. Five minutes of verification beats five days of correction.