A guide to latches

Secure latches on rows of data centre server cabinets

Types of latches and their purpose

All latches keep doors, panels and other surfaces closed with a locking mechanism. Where they differ is in their actuation – the mechanism by which the latch closes – and holding type. You can even get a door lock latch, meaning your latch can lock for added security.

With so many different specialised latches available, and confusion with questions such as what is a door latch is and what are bolt latches, we've put together this guide to help you understand the different types of latches and which best suits your application.

So, whether it's door latches, trigger latches, spring latches, non-locking latches or thumb latches and tubular latches you require, this article will provide the information you need when choosing your latch assembly. We'll cover:

Types of latches
How latches can protect applications against ingress
How latches can minimise vibration and noise
Latches by industry

Types of latches

Cam latches

These are simple mechanical devices that lock, consisting of both a base and a cam lever. Sometimes referred to as a cam lock latch, it’s actuated by turning the base with a key or other tool, which presses the doors or surfaces shut. Mountings vary, from concealed to wings and knobs. You can even get them with T-Handles with a stainless steel cam lock. Cam latches are the most popular cabinet latch hardware.

Compression latches

Compression latches are a type of cam latch but deserve a spotlight of their own. When compression latches close, they compress gaskets against door and panel openings, providing a tight seal. They open via a trigger release mechanism. You either press a button or turn the key, which releases the locking arm. Similar to cam latches are swell latches, which compresses a type of vibration isolator called a rubber bushing,

You can get fixed-compression latches where the cams are fixed to provide consistent compression and decompression to your specified depth. Or, you can go with adjustable compression latches, which lets you change the locking cam’s position. This enables you to adjust compression over a period of time.

Slam latches

This is essentially a spring loaded latch, though sometimes they’re called a push-to-close latch or referred to as having push lock fittings. A specially designed spring provides tactile resistance. As the panel door is pushed, the cam rises and then springs down behind the panel wall, automatically locking doors or panels when closed. A good example of this is a quarter turn slam latch. Quarter turn means that the latch can be opened and closed with 90˚ of rotation.

magnetic cabinet latch, or catch, is another type of push-to-close mechanism. Magnetic forces keep surfaces closed while providing an aesthetic appearance. Simply push to open the surfaces.

Draw latches

Also called pull-down latches and toggle latches. The draw latch has two parts to it. On one side is an arm, which clasps the other side. As the latch closes, the clasp merges the two parts together. What’s going on is simple. Pivoting levers and drawbars reach onto catches to shut the surfaces. This creates a tight seal, especially if you’re using a gasket between the surface and the frame.

This type of latch varies. You can get a heavy duty draw latch, a slide spring draw latch, and a premium draw latch, which provides a high-strength body.

Sliding latches

Components overlap with sliding latches. Again, it’s simple. Actuation is manual. For instance, sliding snap latches require a quick slide movement to the catch, which keeps the surfaces closed, resisting shock and vibration.

View our range of latches

Latches on industrial machine equipment

How latches can protect applications against ingress

Latches can provide the solution for common problems with applications. Consider an outdoor electrical enclosure, outdoor utility cabinet or an outdoor telecom equipment cabinet. These applications must be protected from dust, debris and moisture ingress. Otherwise, performance will suffer. And it’s not just the elements you have to think about, but security as well. This is where a latch can help.

First, if your cabinet or enclosure will be outside, the components you use should be either NEMA or IP rated. That goes for your latches. NEMA electrical enclosures aren’t really different from IP enclosures. Both define degrees of protection against substances, such as water and dust. NEMA, the National Electrical Manufacturer’s Association sets standards used in the U.S., while IP ratings are used in Europe. However, the two are appearing in products in both regions, so it’s a good idea to become familiar with both. You can see more information on how IP and NEMA ratings compare here.

Enclosure door latch on an outdoor generator

 

Solutions for outdoor applications Why
Quarter turn latches Rated IP 65
Good compression for better seal and noise isolation
Adjustable compression latches Rated IP 65
Offers security by locking
NEMA rated, non-locking option
Good compression to seal against ingress and isolate noise
Can change cam lock’s position to adjust for compression over time
Fixed compression latches Rated IP 65
Offers security by locking
Good compression to seal against ingress and isolate noise
Key turns 180˚
Mini adjustable compression latches Rated IP 65
Ideal for limited space
Offers security by locking
Supplied with sealing gasket for good compression and noise isolation
Thick door quarter turn latches Rated IP 65
Ideal for limited space
Offers security by locking
Supplied with sealing gasket for good compression and noise isolation

Why compression is important

Compression latches prolong the life of the equipment you’re housing. By compressing the gasket that surrounds the enclosure opening with consistent force, you’re closing the gaps that otherwise would allow insects, dirt or water inside.

Engineer adjusting some cabinet latch hardware

How latches can minimise vibration and noise

Industrial generator parts, HVAC system components – industrial machinery is rarely quiet. For example, HVAC components, namely the rotating equipment and air and fluid that moves through ducts and pipes, create vibration and noise. Vibration can loosen mounting hardware over time so that it falls off, which can cause damage and leave the application exposed.

It’s not just industrial machinery that has to stand up to the rigours of vibration, but also appliances, and electronic enclosures – even a data cabinet has to handle the jarring impact of vibration. Understand more about the importance of reducing vibrations in our guide to anti-vibration mounts.

Solutions for vibration and noise Why
Latches from Table 1 Compression latches withstand vibration
Adjustable T Handle with compression Compression sealing
T Handle style provides sure grip
Swell latches Compresses a rubber bushing upon closing to resist vibration
Sliding snap latches Sliding snap latches Spring action resists opening under vibration and shock load
Engineer testing different types of latches

Latches by industry

Which latches are popular with your industry?

Automotive

Safety and better tactile feel for opening and closing doors and panels.

Swell latches Vibration resistant
Sliding snap latches Does not open under vibration
Compression latches Vibration resistant

 

HGVs, Construction vehicles and other commercial vehicles

Flush cup recessed T handle latch Heavy duty door latch
Also ideal for railway
Rugged design and construction
For flush mounting
Ample grip for actuation
Locking paddle latch Also ideal as a trailer door locking latch
Secure closure with quick opening
Sliding snap latches Remains closed during vibration

 

HVACs

Enhance industry functionality.

Draw latch, over centre compression Latch arm extends over pin where lever rotates, preventing accidental opening
Compression latches Withstands vibration
Flush cup recessed T handle latch Industrial door latch
Rugged design and construction
For flush mounting
Ample grip for actuation
Mini adjustable compression latches Perfect when space is limited

 

Indoor cabinets

Lift and turn cam latches, also known as swing handles Handle stows away when not in use, avoiding catching clothes or skin
Adjustable T handle with compression Withstands vibration
Ergonomic grip
Sliding snap latches Remains closing during vibration
Quarter turn latches Rubber gasket provides good seal
Economical
Available with wing knobs with extra long housing for sound-proof or isolated doors
Draw latches, also called toggle latches Quick action closure
Swell latches Vibration resistant
L Handle turn cam latches Ample grip for easy actuation
Ergonomic
T Handle turn cam latches Ample grip for easy actuation
Ergonomic

 

Machinery covers

Isolate noise and vibration to minimise malfunctions.

Lift and turn cam latches Handle stows away when not in use, avoiding catching clothes or skin
L Handle turn cam latches Ample grip for easy actuation
Ergonomic
T Handle turn cam latches Ample grip for easy actuation
Ergonomic
Swell latches Vibration resistant
Draw latches, also called toggle latches Quick-action closure
Compression latches Withstands vibration
Sliding snap latches – ideal for small machinery covers Remains closed during vibration

 

Outdoor enclosures

Control access and minimise repair costs.

IP65 rated compression latches Prevents dust and water ingress
Premium draw latch and keeper Robust performance and durability
Cylinder locking quarter turn latches Rated IP 65
Cylinder lock resists tampering
Good compression for better seal and noise isolation

 

Boxes and containers

Quick, easy access.

Draw latches, also called toggle latches Quick action closure
Wire loop latches Quick and easy to use

 

Download free CADs and try before you buy

Free CADs are available for most solutions, which you can download. You can also request free samples (some exclusions apply) to ensure the product you’ve chosen is exactly what you need. 

If you’re not quite sure which solution will work best for your application, our experts are always happy to advise you.

Request your samples or download free CADs now.

Questions?

Email us at sales@essentracomponents.co.uk or speak to one of our experts for further information on the ideal solution for your application 0345 528 0474.