This page explains why the CG-1500 and HC-2500 enclosures do not require a gasket. First we should start with the CG-1500 or the "Cable Guard 1500 Coax CATV Enclosure". This enclosure was sold millions and was originally designed for the cable TV market and is used by all major cable companies. Around 2005, this enclosure, due to its low cost and ubiquitous nature was 'adopted' by the holiday lighting community and around 2010, HolidayCoro also adopted this enclosure for our assembled controller products. We used the CG-1500 for some time and over time we came to see limits in the CG-1500 in the following areas:
- Not large enough for two power supplies which was becoming more common
- Poor mounting options for the door
- Foam cable feeds at the bottom which were not conductive to cable clamps
- Curved door with ribbing
- No method to use pre-drilled end-plates for easier and faster builds
- Insufficient areas for application of build and marketing stickers
- Hard to obtain consistent shipments of product / long lead times
- Poor and inconsistent quality
- No security latch and a bolt for 'locking' the door
We did like other aspects of the CG-1500:
- The highest level 5VA fire resistance
- High levels of UV resistance with some chalking
- Low cost and lack of assembly costs
- Good mounting methods (screw through case and pole clamp)
- Good water resistance
We attempted to work with the manufacturer to develop a new enclosure that would meet our needs but we unsuccessful in convincing them to complete a new design. That didn't stop us, so we gathered up all the good things and left out all the bad things and created a completely new enclosure called the HC-2500. This enclosure also added new features:
- Two latches instead of one for a more secure closing along with a hasp for locks where needed
- Two versions - a solid bottom (for DIY customer drilled holes) and open bottom (for pre-drilled end-plates)
- Stronger polycarbonate material
- Higher UV resistance
- The same mounting boxes on the base and door so the same mounting board can be used on both
- The same mounting bosses as the CG-1500 so all items designed for the CG-1500 into the HC-2500
- Direct molding and assembly by HolidayCoro to improve availability and quality
We are sometimes asked - why don't the CG-1500 and HC-2500 comes with a 'gasket'. This starts with why a sealed enclosure isn't a good as you might think. Conventional thinking is that if you want something to be 'waterproof' is to seal it up tight and for some cases this makes sense - in areas subject to use underwater or where spraying water is present - yep, makes perfect sense. This functionality comes at a cost - this is because all cables and holes must be 100% sealed and this requires more complex connectors, bulkhead fittings and screws but again, if this is a requirement the cost is just a requirement. Additionally, a completely sealed unit is impossible to vent and this is where the real problems come in. A 100% sealed unit will trap in heat since no air exchanges can be made and so typically a these enclosures will be much larger to allow for more void space. Additionally, when the door is closed and the air trapped inside, humidity can also be trapped inside. When the outside temp drops, that humidity will condense and result in water inside the enclosure. In a vented enclosure, the air will exchange and the humidity will equalize even in high RH environments, preventing condensing water inside the enclosure.
To that end, the CG-1500 and HC-2500 both have an interlocking lid to base interface. This interface, combined with the lip on the door and a drip rail prevent water from entering the enclosure when the enclosure is properly mounted in a vertical orientation. We have no documented cases of water infiltration into the HC-2500 when mounted correctly. Additionally, you will find many examples of unsealed enclosures as nearly all outdoor high voltage enclosures and meter cans are not sealed enclosures.
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