Skip to Content
Last modified by Alexander Mott on 2024/01/05 18:55
From version 14.1
edited by Alexander Mott
on 2022/04/15 20:13
Change comment: There is no comment for this version
To version 12.1
edited by Alexander Mott
on 2022/04/14 17:20
Change comment: Uploaded new attachment "1649956845393-707.png", version {1}

Summary

Details

Page properties
Title
... ... @@ -1,1 +1,1 @@
1 -Phase Dimming Troubleshooting
1 +Phase Dimming Troubleshooting (WIP)
Content
... ... @@ -10,31 +10,68 @@
10 10  
11 11  Phase dimming is one of the most common dimming methods for LED fixtures. The term "phase dimming" actually encompasses several dimming technologies which all operate on the same basic principal of chopping up the AC voltage being delivered to the fixtures or drivers.
12 12  
13 -Phase dimming can be broadly divided into two categories: forward phase dimming and reverse phase dimming. Forward phase dimming operates by cutting off the front (leading edge) of the AC sine wave, while reverse phase dimming cuts off the back (trailing edge) of the AC sine wave. See the [[real world data>>WebHome||anchor="HRealWorldPhaseDimmingData"]] below for an illustration.
13 +Phase dimming can be broadly divided into two categories: forward phase dimming and reverse phase dimming. Forward phase dimming operates by cutting off the front (leading edge) of the AC sine wave, while reverse phase dimming cuts off the back (trailing edge) of the AC sine wave. See the //[[real world data>>WebHome||anchor="HRealWorldPhaseDimmingData"]]// below for an illustration.
14 14  
15 15  In the event that phase dimming fixtures are exhibiting unexpected dimming behavior, an easy place to begin troubleshooting is at the lighting control module.
16 16  
17 17  = Verifying Module Output =
18 18  
19 -Crestron produces a variety of phase dimming lighting controllers, and the specifics for troubleshooting them varies slightly. That being said, there is a general procedure for testing phase dimming modules that is applicable to any type of phase dimming controller (even non-Crestron controllers). This general procedure is as follows:
19 +Crestron produces a variety of 0-10V lighting controllers, and the specifics for troubleshooting them varies slightly. That being said, there is a general procedure for testing 0-10V dimming modules that is applicable to any type of 0-10V controller (even non-Crestron controllers). This general procedure is as follows:
20 20  
21 21  1. Identify the module and output that should be dimming the fixtures
22 -1. Disconnect the switch leg to the fixture
23 -1. Connect a multimeter to the switch leg output of the module
24 -1. Measure the V AC output at various brightness levels
22 +1. Disconnect the 0-10V wiring to the fixtures
23 +1. Connect a multimeter to the 0-10V dimming output of the module
24 +1. Measure the 0-10V output at various brightness levels
25 25  1*. If the system has been partially or fully commissioned, it may be possible to use the showrunner™ UI to adjust the brightness
26 26  1*. Alternatively, some modules have physical buttons that can be used to adjust their brightness:
27 27  1**. Press the button to toggle the output on or off. A small LED light on the module will indicate current output on/off status.
28 28  1**. Once the output is on, press and hold the button to cycle dim the output (first press and hold will lower the output, subsequent press and holds will toggle between raising and lowering the output)
29 -1. The measured V AC should decrease with lower brightness levels, but does not necessarily have a linear relationship to the brightness (e.g., output at 20% brightness will be a lower voltage than at 100% brightness, but will not necessarily be 20% of the voltage).
30 -1*. Chief Integrations has recorded actual AC outputs for a few different 120V Crestron modules, available at the bottom of this article.
29 +1. The 0-10V output should roughly correspond to the percentage brightness, e.g. a 60% bright output should be approximately 6V DC
30 +1*. Chief Integrations has recorded actual 0-10V outputs for a few different Crestron modules, available at the bottom of this article.
31 31  
32 +Below is a table of how to interpret troubleshooting results:
33 +
34 +|(% style="width:209px" %)**Result**|(% style="width:321px" %)**Interpretation**|(% style="width:453px" %)**Next Steps**
35 +|(% style="width:209px" %) |(% style="width:321px" %) |(% style="width:453px" %)(((
36 +
37 +)))
38 +|(% style="width:209px" %) |(% style="width:321px" %)(((
39 +
40 +)))|(% style="width:453px" %)(((
41 +
42 +
43 +
44 +)))
45 +
32 32  = Verifying Fixture Wiring and Compatibility =
33 33  
34 34  == Troubleshooting Phase Dimming Wiring ==
35 35  
36 -There are a number of wiring and hardware issues that may result in fixtures not behaving as expected. If fixtures are flickering rapidly as they are dimmed, then fixture compatibility with the dimming module should be verified. Check for incorrect wiring in the field by powering off the circuit for the fixtures, disconnecting the wiring from the module to the fixtures, and then powering the circuit back up. If the wires going to the fixtures still have voltage on them, then they are receiving power from some other source besides the module, which will result in dimming and control issues.
50 +There are a number of wiring and hardware issues that may result in fixtures not behaving as expected. Described below are some techniques that can help determine issues with wiring or hardware, however due to the wide variety of available fixtures and drivers it is not comprehensive.
37 37  
52 +1. Identify the module and output that should be controlling the fixtures
53 +1. Disconnect the 0-10V wiring to the fixtures
54 +1. Toggle the module output on and off to verify it is switching the correct zone
55 +1*. If the system has been partially or fully commissioned, it may be possible to use the showrunner™ UI to toggle the module output
56 +1*. Alternatively, some modules have physical buttons that can be used to toggle the output:
57 +1**. Press the button to toggle the output on or off. A small LED light on the module will indicate current output on/off status.
58 +1**. Once the output is on, press and hold the button to cycle dim the output (first press and hold will lower the output, subsequent press and holds will toggle between raising and lowering the output)
59 +1. While the fixtures are turned off, verify that the voltage on the 0-10V wiring to the fixtures is close to 0 V
60 +1. While the fixtures are turned off, check the 0-10V wiring to the fixtures for shorts
61 +1. While the fixtures are turned on, verify that the voltage on the 0-10V wiring to the fixtures is close to +10 V DC
62 +1. While the fixtures are turned on, short the positive and negative dimming wires to the fixtures
63 +1*. Most drivers will dim to 50% brightness, though some fixtures will turn off
64 +1. Reconnect the 0-10V wiring to the fixtures to the module output
65 +1. Verify the module output voltage while the fixtures are connected
66 +1*. The module output should be similar to the module output while the fixtures are disconnected
67 +
68 +Below is a table of how to interpret troubleshooting results:
69 +
70 +|(% style="width:273px" %)**Result**|(% style="width:317px" %)**Interpretation**|(% style="width:393px" %)**Next Steps**
71 +|(% style="width:273px" %) |(% style="width:317px" %) |(% style="width:393px" %)
72 +|(% style="width:273px" %) |(% style="width:317px" %) |(% style="width:393px" %)
73 +|(% style="width:273px" %) |(% style="width:317px" %) |(% style="width:393px" %)
74 +
38 38  == Determine Fixture Compatibility ==
39 39  
40 40  (% class="wikigeneratedid" %)
... ... @@ -41,65 +41,62 @@
41 41  If the fixtures are misbehaving but the wiring has been verified correct, then there may be compatibility issues between the fixture, the driver, and the lighting controller.
42 42  
43 43  (% class="wikigeneratedid" %)
44 -Crestron maintains a [[list of compatible drivers>>https://www.crestron.com/Support/Tools/Lighting/Lighting-Fixture-Compatibility-List]] on their website. Determine the fixture and driver that have been installed and verify they are compatible with the phase dimming lighting controller being used.
81 +Crestron maintains a [[list of compatible drivers>>https://www.crestron.com/Support/Tools/Lighting/Lighting-Fixture-Compatibility-List]] on their website. Determine the fixture and driver that have been installed and verify they are compatible with the 0-10V lighting controller being used.
45 45  
46 46  (% class="wikigeneratedid" %)
47 -Verify that the LED drivers are actually phase dimming drivers and not 0-10V, non-dimming, DALI, or some other dimming drivers. If the drivers are not phase dimming control drivers, then it will not be possible to dim the fixtures using a phase dimming module unless the drivers are changed out for phase dimming drivers.
84 +Verify that the LED drivers are actually 0-10V drivers and not phase dimming, non-dimming, DALI, or some other dimming drivers. If the drivers are not 0-10V control drivers, then it will not be possible to dim the fixtures using a 0-10V module unless the drivers are changed out for 0-10V drivers.
48 48  
49 49  (% class="wikigeneratedid" %)
50 -Verify that the type of phase dimming required (forward or reverse) matches the type of phase dimming being output by the module. Many Crestron modules are universal phase dimming which should auto-detect the required dimming, but sometimes it will detect the incorrect dimming and must be forced to the correct mode. Consult the installation guide for each module to determine how to check and force the dimming mode.
87 +There are two types of 0-10V LED driver: constant current and constant voltage. Constant current drivers dim the LED fixtures by varying the voltage output to reduce power while keeping current constant. Constant voltage drivers dim the LED fixtures by rapidly pulsing a constant voltage output. If the incorrect type of driver is used to power the fixtures (e.g. a constant current driver used for fixtures which require constant voltage), then the fixtures will not dim correctly. Verify that the drivers used are compatible with the fixtures.
51 51  
52 -(% class="wikigeneratedid" %)
53 -It is also possible that there is a compatibility issue between the LED driver and the fixture. There are two types of LED driver: constant current and constant voltage. Constant current drivers dim the LED fixtures by varying the voltage output to reduce power while keeping current constant. Constant voltage drivers dim the LED fixtures by rapidly pulsing a constant voltage output. If the incorrect type of driver is used to power the fixtures (e.g. a constant current driver used for fixtures which require constant voltage), then the fixtures will not dim correctly. Verify that the drivers used are compatible with the fixtures.
54 -
55 55  = Specific Crestron Modules =
56 56  
57 -The below sub-sections cover specific dimming procedures for various phase dimming controllers produced by Crestron.
91 +The below sub-sections cover specific dimming procedures for various 0-10V controllers produced by Crestron.
58 58  
59 59  == CLX-2DIMU8 and CLX-2DIMU8-277 ==
60 60  
61 -Phase dimming CLX modules are installed inside CAEN panels, which are typically located inside an electrical room or an MDF/IDF closet.
95 +Zūm Wired JBOXs mount to a 1/2" knockout of a standard junction box.
62 62  
63 -Each CLX module has eight outputs split into two groups: outputs 1 through 4 are in the first group, while outputs 5 through 8 are in the second group. Even if there are no loads in the first group of outputs, the module still requires a line voltage input in order to function. The second group of loads will appear to be able to be toggled on and off, but the outputs will not change unless the second group of outputs is receiving a line voltage input. The line voltage input for the second group of outputs does not need to be on the same circuit as the line voltage input for the first group, but it must be on the same phase.
97 +Inside the junction box will be two flying leads for the 0-10V dimming output. The grey lead is for the negative output and the violet lead is for the positive output. These leads should be wire nutted or lever nutted with the wiring to the fixtures. The leads should disconnected from the fixtures during troubleshooting.
64 64  
65 -On the front of 0-10V CLX modules are eight LEDs corresponding to each of the eight outputs. Above these LEDs are two buttons which can be used to toggle each output individually, view the current dimming mode, and switch the dimming mode for each output. There is no way to dim individual outputs from the module; the system must be at least partially commissioned with a functioning processor in order to verify dimming functionality.
99 +On the front of the Zūm JBOX-16A-LV (outside the junction box) are two or three LEDs next to a black button. The LED labeled "TEST" will be green if the output is hot. The black button can be used to toggle the output on or off, and holding the button will cycle dim the 0-10V output.
66 66  
67 67  See //[[Figure 1>>WebHome||anchor="HFigure1"]]// for details.
68 68  
69 69  == GL-EXP-DIMU-CN ==
70 70  
71 -GL-EXP-DIMU-CN are single-channel expansion modules used to provide additional phase dimming control to a system. They are self-contained and are surface mounted directly to a wall or ceiling.
105 +0-10V CLX modules are installed inside CAEN panels, which are typically located inside an electrical room or an MDF/IDF closet.
72 72  
73 -LEDs on the module face indicate the current phase dimming mode, while dip-switches inside the module can be used to force the module into either forward or reverse phase dimming mode.
107 +Each CLX module has eight outputs split into two groups: outputs 1 through 4 are in the first group, while outputs 5 through 8 are in the second group. Even if there are no loads in the first group of outputs, the module still requires a line voltage input in order to function. The second group of loads will appear to be able to be toggled on and off, but the outputs will not change unless the second group of outputs is receiving a line voltage input. The line voltage input for the second group of outputs does not need to be on the same circuit as the line voltage input for the first group, but it must be on the same phase.
74 74  
75 -In order to access the phase dimming output, the front of the module must be removed. Inside the module is a paper barrier separating the high voltage output (on the left) from the low voltage control wiring (on the right). A small flathead screwdriver is required to disconnect the high voltage wiring to the fixtures.
109 +On the front of 0-10V CLX modules are eight buttons corresponding to each of the eight outputs. Next to each button is a red LED indicating the current load status. The LED will be lit if the output is on. To the right of the LED is the 0-10V output for each channel, which can be easily unplugged for troubleshooting. The buttons can be used to toggle each channel independently, and holding the button will cycle dim the 0-10V output for that channel.
76 76  
77 -The "ON/OFF" light on the front of the module indicates the current output status (red means the output is on), and the button next to it can be used to toggle the output on or off. Press and hold the button to cycle dim the phase dimming output.
78 -
79 -The ON/OFF button sits proud of the module cover, so care must be taken when replacing the cover to avoid damaging the button.
80 -
81 81  See //[[Figure 2>>WebHome||anchor="HFigure2"]]// for details.
82 82  
83 83  == DIN-1DIMU4 ==
84 84  
85 -Phase dimming DIN-1DIMU4 modules are installed inside DIN panels, which are typically located inside an electrical room or an MDF/IDF closet.
115 +GL-EXP-DIMFLV-CN are single-channel expansion modules used to provide additional 0-10V control to a system. They are self-contained and are surface mounted directly to a wall or ceiling.
86 86  
87 -Each DIN-1DIMU4 module has four outputs which all share a common line input. Each output has corresponding LEDs to indicate current output status and current phase dimming mode. Each output also has a corresponding button which can be used to toggle each channel independently, and holding the button will cycle dim the phase dimming output for that channel.
117 +In order to access the 0-10V output, the front of the module must be removed. Inside the module is a paper barrier separating the high voltage switched output and 0-10V dimming (on the left) from the low voltage control wiring (on the right). A small flathead screwdriver is required to disconnect the 0-10V wiring to the fixtures.
88 88  
119 +The "ON/OFF" light on the front of the module indicates the current output status (red means the output is on), and the button next to it can be used to toggle the output on or off. Press and hold the button to cycle dim the 0-10V output.
120 +
121 +The ON/OFF button sits proud of the module cover, so care must be taken when replacing the cover to avoid damaging the button.
122 +
89 89  See //[[Figure 3>>WebHome||anchor="HFigure3"]]// for details.
90 90  
91 91  = Real World Phase Dimming Data =
92 92  
93 -Below is a table of actual phase dimming readings at various percentage brightness for some Crestron lighting controllers. Measurements were taken from 120V modules using a true-RMS meter (note that the oscilloscope graph appears high because it is reading the peak voltage).
127 +Below is a table of actual 0-10V readings at various percentage brightness for some Crestron lighting controllers:
94 94  
95 -|=(% style="width: 99px;" %)Percentage Brightness|=(% style="width: 764px;" %)CLX-2DIMU8 Oscilloscope Output|=(% style="width: 119px;" %)CLX-2DIMU8 Reading (V AC)
96 -|(% style="width:99px" %)100%|(% style="width:764px" %)[[image:1649956710772-275.png]]|(% style="width:119px" %)~~118
97 -|(% style="width:99px" %)80%|(% style="width:764px" %)[[image:1649956722651-285.png]]|(% style="width:119px" %)~~112
98 -|(% style="width:99px" %)60%|(% style="width:764px" %)[[image:1649956734539-236.png]]|(% style="width:119px" %)~~97
99 -|(% style="width:99px" %)50%|(% style="width:764px" %)[[image:1649956742753-637.png]]|(% style="width:119px" %)
100 -|(% style="width:99px" %)40%|(% style="width:764px" %)[[image:1649956753212-813.png]]|(% style="width:119px" %)~~74
101 -|(% style="width:99px" %)20%|(% style="width:764px" %)[[image:1649956765039-459.png]]|(% style="width:119px" %)~~47
102 -|(% style="width:99px" %)0%|(% style="width:764px" %)[[image:1649956845393-707.png]]|(% style="width:119px" %)~~0.005
129 +|=Percentage Brightness|=GLPP-1DIMFLV2CN-PM Reading|=GLPAC-DIMFLV8 Reading|=GLXP-DIMFLV8 Reading
130 +|100%|9.94 V|10.03 V|10.00 V
131 +|80%|8.02 V|8.09 V|8.08 V
132 +|60%|5.96 V|6.13 V|6.11 V
133 +|50%|4.98 V|5.10 V|5.04 V
134 +|40%|4.01 V|4.06 V|4.02 V
135 +|20%|1.98 V|2.09 V|2.06 V
136 +|0%|27.1 mV|33.2 mV|25.4 mV
103 103  
104 104  
105 105  )))