Cable DMX512. Standard cables for the DMX 512 signal.

A robust DMX512 system starts with high quality cables of a certain type. If the reliability of the system is very important, then first of all you should pay attention to the cables and connectors, and also to their correct installation. You can build a DMX system and use second-rate cables (and even ordinary electrical wires like those that go to your electric bell), however on one nightmarish day such a system can suddenly fail without any visible Reasons in the midst of an important show.

The cable must comply with the EIA485 standard (RS485) and consist of one or two low-capacitance twisted pairs, braided and screened with foil. In order for the wires to have sufficient mechanical strength and minimum voltage drop on long lines, they must correspond to the American wire gauge of 24 AWG (7 / 0.2) or higher.

The second pair of wires can be present in the cable as a spare, or can be used to transmit other signals. Some dimmers use this pair to report faults and the status of the dimmer. Check if your DMX uses the second pair (currently, in most cases, this pair is not used).

When you are wiring for permanent use, it is recommended that you use cables with at least two twisted pairs in order to be able to use these lines with future versions of the DMX512 protocol. Currently, some manufacturers are already releasing systems using a second twisted pair to transfer information from dimmers to the console. In addition, the additional twisted pair will not interfere if there is an open or short on the main pair.

The cable shield is connected to the pins of connector 1. The first (main) twisted pair is connected to pins 2 and 3. The second twisted pair (if any) is connected to pins 4 and 5. The screen MUST be connected at both ends of the cable even if the receiver is not grounded. Otherwise, the cable will not be shielded.

The screen MUST NOT be connected or in contact with any other part of the connectors (for example, with the case), because Usually the connector housings are connected to the ground supply voltage, and such a connection will lead to problems related to contour earth currents (see subsection “Grounding”).

Cable types.

The “Cable Type Table” in the appendix at the end of this manual is not a complete list of all cables that may be suitable for use with the DMX512. For this purpose, any twisted-pair cable with a wave impedance of 120 Ohms, shielded and conforming to the EIA485 standard, is suitable. The cable assortment required will depend on the length of the line, but it is recommended to use cables with ordinal numbers of at least 22 AWG, 24 AWG.

AWG stands for American Wire Gauge. H E

Cable Table

Cable Type Table

Type: Pairs: ZW: Jacket: AWG Use: Temp:
Belden cables:
1162A 1 100 PVC 20 UL2498 80
1215A 2 150 PVC 26 IBM type 6 office cable 75
1269A 2 100 PTFE 22 (solid) High temp, Plenum cable 200
8102 2 100 PVC 24 UL2919 80
8132 2 120 PVC 28 UL2919 80
8162 2 100 PVC 24 UL2493 ​​60
8227 1 100 PVC 20 UL2498 80
82729 2 100 PTFE 24 High temp, Plenum cable 200
88102 2 100 PTFE 24 High temp, Plenum cable 200
89182 1 150 PTFE 22 High temp, Plenum cable 200
89207 1 100 PTFE 20 High temp, Plenum cable 200
89696 2 100 PTFE 22 High temp, Plenum cable 200
89729 2 100 PTFE 24 High temp, Plenum cable 200
89855 2 100 PTFE 22 High temp, Plenum cable 200
9182 1 150 PVC 22 UL2668 60
9207 1 100 PVC 20 Flame-proof 75
9271 1 124 PVC 25 UL2092 60
9729 2 100 PVC 24 UL2493 ​​60
9804 2 100 PVC 28 UL2960 60
9829 2 100 PVC 24 UL2919 80
9841 1 120 PVC 24 UL2919 80
9842 2 120 PVC 24 UL2919 80
Proplex cables:
PC222P 1 110 Polyurethane 22 Heavy duty and portable 105
PC222T 1 110 PVC 22 UL2464 105
PC224P 2 110 Polyurethane
PC224T 2 110 PVC 22 UL2464 105
PC226T 3 110 PVC 22 UL2464
Alpha cables:
9109 1 100 FEP 20 High temp 150
9816 1 95 PVC 18 Large diameter 80
9817 1 100 PVC 20 UL2498 80
9818 1 100 PVC 20
9818D 1 100 Polyurethane 20 Direct burial 80
9821 1 124 PVC 25 UL2092 80
9823 1 150 PVC 22 UL2772 ​​ 80

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