Ltl Acorn 6210 Water Resistance Tests

Ltl Acorn 6210MMX

Don't all die of shock. This is what we've all been waiting for.
A 6210 with a water tight case.

Camera under test: 

Ltl Acorn 6210MG S/N 202001037 – This test camera is the re-designed case as of October 2012

Purpose of test: 

To determine its resistance to water ingress during heavy rainfall with at least a ten degrees centigrade drop in case temperature during the first five minutes from the start of the test.

Reason for test:

The camera case is a sealed unit at normal air pressure but with any sudden drop in external case temperature (e.g. cold heavy rain following heating by sun), the air inside starts to contract and form a vacuum. As the vacuum increases any weakness in the case seals will cause the seal to break down at some point and
suck in air from the outside. Any water collecting around an area where the seal collapses will be sucked inside the case. If the pressure differential is sufficient the water will form a spray inside the case which will quickly saturate the internal area, including the control panel.

History:

Control panel and inside of bottom door assembly

Previously these cameras have had design issues where small case mould imperfections caused a seal weakness at the rear of the case adjacent to the bottom door and hinge. In addition, because of insufficient sinking around the door hinge, water was collecting in this area. If a vacuum formed inside the case, the door seal would break down and the collected water would be sucked inside the case, where it quickly saturated the control panel.

This is not much of a problem in climates where the rain and air temperatures are similar; but in climates where the temperature of the rain can be significantly lower than that of the air, and where sudden heavy rain follows heating by the sun, an internal vacuum is quickly formed.

Consequently, in Oceanic climates, users experienced continual problems resulting in saturation of the control panel and rendering the camera unusable, until it had been thoroughly dried.

Following a series of case mould modifications by the Acorn factory, between June and October 2012 this final design is intended to correct the above problem.

Test Set Up:

Cameras under test

Top Camera:

6210MG s/n 202001037
October 2012 case design




Bottom Camera:

6210M   s/n 109005164
August 2012 case design
This camera tested OK previously and was used as a benchmark for this test

Method:

Warm camera to approximately 40 degrees centigrade and place on post.
Measure temperature before spraying.
Spray for two minutes.
Measure temperature drop.
Spray for further five minutes.
Measure temperature drop.
Spray for further five minutes.

Test Conditions:

Variable air temperature between 0C and 10C over three days. Sunshine and showers.

Test Results:

Test 1) 

6210MMX External Antenna Socket

During the first test the antenna socket on top of the camera leaked water into the top of the case during a temperature drop of approximately 20C. Retaining nut was screwed directly onto the rubber sealing washer which resulted in uneven compression of the washer and only a partial seal.

This was corrected by placing a very thin stainless steel washer between the retaining nut and the rubber sealing washer.

The steel washer needs to be of minimal thickness and the rubber washer requires good compression to ensure a seal; and to allow sufficient thread for the external antenna to screw down far enough to make a contact.

Test 2)

Effect of water in control panel

With a similar temperature drop to test 1, the antenna seal held. The bottom door was opened immediately after a ten minute spray.

Water had collected around the case and had not been allowed to run off. When the door was opened, the internal vacuum was strong enough to suck water into the inside of the case, in sufficient quantity to enter the control panel.

This initially caused erratic menu commands and then vertical lines on the screen as shown left. After drying all functions returned to normal with no lasting effect.


Test 3) to Test 6) Four more tests were conducted and after each test the outside of the camera case was dried off before opening the bottom door.

No water had entered the case during tests 3 to 6.

Immersion test: 

Acorn 6210 test camera fully submerged

This camera is manufactured to IP54 which means dust and splash resistant, which it clearly is, as shown by the earlier tests. It is not classed as waterproof, but following the success of the rain tests, I wanted to see how resistant to water entry the camera is.

For this test the camera was immersed in 130cm of water for one minute as illustrated left.

With a full set of batteries inserted, these cameras do not float.

Water temperature 24C.
Cameras internal case temperature 37C.

After one minute the camera was removed from the water and dried off.

Acorn 6210 after submersion

When the bottom door was opened only a very small amount of water had entered, and was not sufficient to cause a malfunction.

There were no lasting effects after drying off.

Clearly this camera will survive immersion providing it is retrieved within the first few minutes, although a thorough drying will be required.

Internal case condensation:

Condensation on the inside of the LED array

During normal use, when the cameras internal temperature is higher than the outside case temperature, condensation will form on the inside of the cameras case.

This condition will occur during and just after heavy rain. Condensation will always show on the inside of the LED array under this condition, as shown left, but I have not seen condensation form on the inside of the lens window.

This is normal and does not cause any lasting effect, damage to internal parts or noticeably affect the performance of the IR lighting.

The water on the lens has collected on the outside after the immersion.

Internal condensation should not be confused with external condensation on the lens. 

Misting of the outside of the lens usually occurs in the early morning through to around sunrise, and is caused by high humidity and/or external heating by the sun, when the case internal temperature is lower than the outside temperature.

This problem is an issue for all trail cameras and similar equipment, when used in an outdoor environment.

The issue can be mitigated by using a water based anti fogging agent, but this will only be effective for about one week.

Conclusions:

With the changes that have been made to the case, this camera now achieves a good resistance to water ingress, under all normal operating conditions for which this type of equipment is intended.

It certainly meets its IP54 rating of dust and splash resistant.

Providing the external antenna socket sealing is achieved and production quality control standards are maintained, this camera is, in my opinion, fit for purpose.

New Software:

Both the 5210 and 6210 series cameras have new software and over the next two to three weeks I'll be doing a complete evaluation of both.

This will also include notes on what settings to use in different circumstances and why to make them, plus how to physically set these cameras up in field situations, to get the most from them.