sitelights
11-03-2004, 07:44 PM
There is a tendency on the part of manufacturers to clone each other's designs. In this post three very common and one very uncommon surface mounted luminaires (deck, step, etc) are examined.
This review, and in fact all of my product reviews have a primary and a secondary purpose. First, they are written to suggest a model for critical analysis that others can apply to products in general: form and function. Second, the product reviews that impart the most information are those that compare similar products from different manufacturers; it is not a question of endorsing one product over another but merely to alert readers to details that I think are important.
All of these products were purchased through normal channels and each of them has at one time or another been installed in quantity.
In the attached image ccounter clockwise from noon: Focus SL-07 (F) cover and mounting plate; the same item flopped; Cast CDL1CB (C) arrayed the same; Escort TR14 (E) in two orientations. The Hadco SRL2 (H) is so similar to the Focus model that there is no point in showing it. The demi-hemispheres are all identical in size and at a glance differ only in the white painted backing plate of the F and H and the non-reflective rough (and soon to be darkened) backing plate of the C. The E is all in one piece and the copper also will darken. The effect of design and its relation to light output is detailed below.
The form of the hemispherical castings and backing plates of the F, C, H are essentially identical so if you have seen one you have seen them all. Sand cast in aluminum, copper, brass, bronze or molded composite these items differ only in socket and lamp type. There are many iterations of this basic fixture since almost every manufacturer makes a version. The F, C, H each have a tempered frosted glass cover siliconed on the inside of the horizontal cut line of the cover. The E is formed of quite heavy gauge (for its size) sheet copper in two pieces that are interlocked and soldered; all edges are minutely folded to strengthen the form. The lamp is not covered on the E and the 10w xenon lamp will not shatter if wetted; this allows light output to equal the output of the 20w Single Contact Bayonet (SCB) lamp on the F and H and exceed the light ouput of the C.
The cover is secured to the base plate by two recessed machine screws that are tightened to achieve a friction fit. The very small screws (do not back them all the way out or they are lost) are either slotted (F, H) or hex (C) head and are not meant to mate with a threaded hole so the cover can be adjusted minimally to fine tune the orientation of the frosted lens if the installation of the base plate is not exact. To me the difference merely means another tool to carry. I have noticed a trend to include the appropriate hex key with certain products (Ikea and others) but with C you're supplying your own easily lost key while a small slotted screwdriver is in everyone's tool box. Lose the key and you have to buy another entire set of at least 7 hex keys to replace the one you lost. In a pinch an appropriately sized common nail point can save you a trip to the tool crib.
My approach to all low voltage landscape products is that of a professional, producing installer not a DIYer. A pro's meter is always running; the DIYer has a whole weekend. I am reminded of an Emily Dickenson poem with the line: "... and at my back I always hear time's winged chariot drawing near...". This line needs to be read as "wing-ed" to scan.
Since the F, C, H, E are functionally different only in the type socket, the socket connection point to the leads and the lamp these details will be treated at length.
The F shown is an early version that I ordered with a bi-pin socket rather than their SCB socket with the hard to find SCB 20w halogen hybrid lamp. The C has the the SCB socket and lamp but the lamp is 10w; the label states "10w max" on the C; the F "25w max" [but there is no SCB 12v 25w halogen or xenon lamp on the market] came with a 20w bi-pin halogen that has been superseded by the same socket/lamp as the C but with a 20w lamp. The SCB halogen in 10w or 20w is not exactly an off-the-shelf item and you will get a blank look if you ask for one at any electrical supply company much less at a big box discount store. Since these lamps are only available from the fixture maker you are limiited to what is, in effect, a proprietary, not readily available replacement. The H was equiped with the SCB socket and 1141 18w automotive type lamp. Of course it is possible to lamp an SCB socket with either the hybrid halogen in 10, 20, 35 and even 50w ouput or the automotive non-halogen SCB in the range of 7 to 35w. In a post "overlamping/underlamping" in the Lamps & Sockets Forum I voice my objection to socket /lamp combinations that can exceed the rating of the fixture; there is nothing to stop a clueless homeowner from creating a hazard. Electric light is 90% heat and 10% light so correct lamping is important; in the trade the lamp filament is referred to as the "burner". The bi-pin jawed socket is sized to limit lamp wattage since the higher watt bi-pin lamps have different pin spacing and pin thickness; the wedge base socket is sized to accomodate T3.25 or T5 lamps and the difference prevents using a higher watt lamp in a lower watt rated socket.
The E has a wedge base socket sized to accept the 911X xenon 11w lamp; the T3.25 socket will accept 3 to 11w xenon lamps in both clear and frosted versions. The E wedge base socket is unlke any others that I've seen in that the jaws are three-sided and really grip the lamp. The usual two-sided wedge base socket allows the lamp to be easily displaced horizontally and is therefore inferior.
The plethora of 12v lamp types has much to do with longevity. The incandescent automotive lamps are rated at about 900 hours (OK for a DIYer who is always on site), the halogens range from 2,000 to 5,000 hours and the xenons up to 20,000 hours. Since a low voltage outdoor lighting system operating dusk to midnight equals about 2,000 operating hours a year (as they say in the car ads "Your mileage may vary.") lamp life is a critical concern for professionals. My lamp life warranty is three years; I pay very close attention to these lamp life estimates. One could search "lamp life" for details.
The F and H sockets are butt spliced unprotected onto the leads; the C socket is actually soldered to the leads and covered with a very tough shrink-wrap type material. The E socket has the leads connected directly to the jaws. The C socket's heavy wrap is covered with a woven black heat resistant tube as a running spec change note that the C plates in the image are of both types. The sockets on the F, C, H could be field replaced using butt splices. The sockets are attached to a "hickey" (an L shaped bracket common to all the sockets) with a rivet so on the E the socket and lead wire must be replaced as a unit since there is no place to put butt splices. The hickey is bolted or machine screwed to the backing plate of each and can
be easily replaced if you have exactly the right part.
All the fixtures can be back fed or surface fed and all have mounting holes; F, C, H have arrows and the word "up" cast into the backing plate to aid the installer since the cover will fit only one way. The C protective material on the earlier version protruded and made it almost impossible to mount flush; the latest version has the material contained within the circumference. The C is also equipped with 25' of 16/2 (the others have 6' of 18/2) and need a large hole to tediously pull all that wire through. We cut it back to 6' or 8' since we are not making a home run to a single giant splice.
These two-piece items can be installed with the frosted lens in any orientation as long as the arrow is pointing opposite of the direction the lens will be aimed. The E is its own arrow and can be mounted 360 degrees although I doubt that the maker intended these little sconces to have their apex pointing downward. I have mounted these "upside down" with no ill effect since the unit drains readily and the xenon lamp won't shatter if a drop of water hits it. The E is mounted using a keyhole and round hole (like those on most transformers) but when pointed down and backwired a bit of tension on the lead when it is stapled will hold the unit in position without screws since it is much lighter than the F and H and much, much lighter than the C. Actually, when the fixture is mounted on a rail of post at a height where it might get bumped, we do mount without screws so it can be displaced on impact. On this point (no pun intended) the fixture is available in a flattened form i.e. in reflected plan view the shape is a trapezoid rather than a triangle, if the point is a problem.
As usual, I will alert each manufacturer of this posting in the event that they might wish to correct any errors of fact or to make comments.
This review, and in fact all of my product reviews have a primary and a secondary purpose. First, they are written to suggest a model for critical analysis that others can apply to products in general: form and function. Second, the product reviews that impart the most information are those that compare similar products from different manufacturers; it is not a question of endorsing one product over another but merely to alert readers to details that I think are important.
All of these products were purchased through normal channels and each of them has at one time or another been installed in quantity.
In the attached image ccounter clockwise from noon: Focus SL-07 (F) cover and mounting plate; the same item flopped; Cast CDL1CB (C) arrayed the same; Escort TR14 (E) in two orientations. The Hadco SRL2 (H) is so similar to the Focus model that there is no point in showing it. The demi-hemispheres are all identical in size and at a glance differ only in the white painted backing plate of the F and H and the non-reflective rough (and soon to be darkened) backing plate of the C. The E is all in one piece and the copper also will darken. The effect of design and its relation to light output is detailed below.
The form of the hemispherical castings and backing plates of the F, C, H are essentially identical so if you have seen one you have seen them all. Sand cast in aluminum, copper, brass, bronze or molded composite these items differ only in socket and lamp type. There are many iterations of this basic fixture since almost every manufacturer makes a version. The F, C, H each have a tempered frosted glass cover siliconed on the inside of the horizontal cut line of the cover. The E is formed of quite heavy gauge (for its size) sheet copper in two pieces that are interlocked and soldered; all edges are minutely folded to strengthen the form. The lamp is not covered on the E and the 10w xenon lamp will not shatter if wetted; this allows light output to equal the output of the 20w Single Contact Bayonet (SCB) lamp on the F and H and exceed the light ouput of the C.
The cover is secured to the base plate by two recessed machine screws that are tightened to achieve a friction fit. The very small screws (do not back them all the way out or they are lost) are either slotted (F, H) or hex (C) head and are not meant to mate with a threaded hole so the cover can be adjusted minimally to fine tune the orientation of the frosted lens if the installation of the base plate is not exact. To me the difference merely means another tool to carry. I have noticed a trend to include the appropriate hex key with certain products (Ikea and others) but with C you're supplying your own easily lost key while a small slotted screwdriver is in everyone's tool box. Lose the key and you have to buy another entire set of at least 7 hex keys to replace the one you lost. In a pinch an appropriately sized common nail point can save you a trip to the tool crib.
My approach to all low voltage landscape products is that of a professional, producing installer not a DIYer. A pro's meter is always running; the DIYer has a whole weekend. I am reminded of an Emily Dickenson poem with the line: "... and at my back I always hear time's winged chariot drawing near...". This line needs to be read as "wing-ed" to scan.
Since the F, C, H, E are functionally different only in the type socket, the socket connection point to the leads and the lamp these details will be treated at length.
The F shown is an early version that I ordered with a bi-pin socket rather than their SCB socket with the hard to find SCB 20w halogen hybrid lamp. The C has the the SCB socket and lamp but the lamp is 10w; the label states "10w max" on the C; the F "25w max" [but there is no SCB 12v 25w halogen or xenon lamp on the market] came with a 20w bi-pin halogen that has been superseded by the same socket/lamp as the C but with a 20w lamp. The SCB halogen in 10w or 20w is not exactly an off-the-shelf item and you will get a blank look if you ask for one at any electrical supply company much less at a big box discount store. Since these lamps are only available from the fixture maker you are limiited to what is, in effect, a proprietary, not readily available replacement. The H was equiped with the SCB socket and 1141 18w automotive type lamp. Of course it is possible to lamp an SCB socket with either the hybrid halogen in 10, 20, 35 and even 50w ouput or the automotive non-halogen SCB in the range of 7 to 35w. In a post "overlamping/underlamping" in the Lamps & Sockets Forum I voice my objection to socket /lamp combinations that can exceed the rating of the fixture; there is nothing to stop a clueless homeowner from creating a hazard. Electric light is 90% heat and 10% light so correct lamping is important; in the trade the lamp filament is referred to as the "burner". The bi-pin jawed socket is sized to limit lamp wattage since the higher watt bi-pin lamps have different pin spacing and pin thickness; the wedge base socket is sized to accomodate T3.25 or T5 lamps and the difference prevents using a higher watt lamp in a lower watt rated socket.
The E has a wedge base socket sized to accept the 911X xenon 11w lamp; the T3.25 socket will accept 3 to 11w xenon lamps in both clear and frosted versions. The E wedge base socket is unlke any others that I've seen in that the jaws are three-sided and really grip the lamp. The usual two-sided wedge base socket allows the lamp to be easily displaced horizontally and is therefore inferior.
The plethora of 12v lamp types has much to do with longevity. The incandescent automotive lamps are rated at about 900 hours (OK for a DIYer who is always on site), the halogens range from 2,000 to 5,000 hours and the xenons up to 20,000 hours. Since a low voltage outdoor lighting system operating dusk to midnight equals about 2,000 operating hours a year (as they say in the car ads "Your mileage may vary.") lamp life is a critical concern for professionals. My lamp life warranty is three years; I pay very close attention to these lamp life estimates. One could search "lamp life" for details.
The F and H sockets are butt spliced unprotected onto the leads; the C socket is actually soldered to the leads and covered with a very tough shrink-wrap type material. The E socket has the leads connected directly to the jaws. The C socket's heavy wrap is covered with a woven black heat resistant tube as a running spec change note that the C plates in the image are of both types. The sockets on the F, C, H could be field replaced using butt splices. The sockets are attached to a "hickey" (an L shaped bracket common to all the sockets) with a rivet so on the E the socket and lead wire must be replaced as a unit since there is no place to put butt splices. The hickey is bolted or machine screwed to the backing plate of each and can
be easily replaced if you have exactly the right part.
All the fixtures can be back fed or surface fed and all have mounting holes; F, C, H have arrows and the word "up" cast into the backing plate to aid the installer since the cover will fit only one way. The C protective material on the earlier version protruded and made it almost impossible to mount flush; the latest version has the material contained within the circumference. The C is also equipped with 25' of 16/2 (the others have 6' of 18/2) and need a large hole to tediously pull all that wire through. We cut it back to 6' or 8' since we are not making a home run to a single giant splice.
These two-piece items can be installed with the frosted lens in any orientation as long as the arrow is pointing opposite of the direction the lens will be aimed. The E is its own arrow and can be mounted 360 degrees although I doubt that the maker intended these little sconces to have their apex pointing downward. I have mounted these "upside down" with no ill effect since the unit drains readily and the xenon lamp won't shatter if a drop of water hits it. The E is mounted using a keyhole and round hole (like those on most transformers) but when pointed down and backwired a bit of tension on the lead when it is stapled will hold the unit in position without screws since it is much lighter than the F and H and much, much lighter than the C. Actually, when the fixture is mounted on a rail of post at a height where it might get bumped, we do mount without screws so it can be displaced on impact. On this point (no pun intended) the fixture is available in a flattened form i.e. in reflected plan view the shape is a trapezoid rather than a triangle, if the point is a problem.
As usual, I will alert each manufacturer of this posting in the event that they might wish to correct any errors of fact or to make comments.