Processing and Control for Professional AV Installations
Legacy Hardware



The number of ARCs that can be daisy chained together will vary depending on the type of ARCs used and the cable lengths.  Download Link: ARC Power Calculator.

Below is a PDF form which can be downloaded to your computer and used to produce labels for your Modular ARC (SW4, SWK, MIC, XLR and EX4 panels). Download the file linked below to your computer. Open the file with Adobe Acrobat. If you do not have Acrobat on your computer, it is freely available from Adobe. Once you have opened the document, you may type directly into the button label fields. The label text will auto-size from one large character to no more than three lines of eight characters each. Once you have typed up the labels you require, you may save your work for future use or print to the printer and paper of your choice..

SW4 Label Template

A single standard straight-through CAT-5/6 cable will provide power and data to an ARC from the host DSP.  The daisy-chain to subsequent ARCs also uses CAT-5/6.

Legacy DSPs that pre-date the ARC Port (RJ-45) communicate to ARCs with a twisted-pair (A, B, Ground) for RS-485 data.  In this scenario a local external transformer provides up to 24VDC to the ARC.

An ARC’s power requirements vary depending on the voltage supplied to it. For example, an ARC-2e at 24V DC uses approximately 55 mA, while at 7V DC it uses approximately 170 mA maximum. As the voltage varies from 24 to 7 VDC, the current requirement increases accordingly. ARCs can be daisy-chained and fed power over this daisy-chain from an ARC-PSe or other device. However, as the length of the cable increases, so does the resistive line loss, which lowers the voltage available at each subsequent ARC. The actual power drain on each output from the powering device can vary substantially depending on the number of ARCs and the distance each of them is separated by. In order to assist with system design, Symetrix has available a Microsoft Excel spreadsheet that can help a system designer determine power requirements based upon cable length, number of ARCs and the power supply to be used.

Download Link: ARC Power Calculator.

One channel of audio can be sent either way.

The ARC Audio port provides a means to either break-in or break-out a single balanced analog audio line from an ARCs CAT5 cable.  Note, not all ARCs support ARC Audio.

The ARC-SWK is a popular wall panel for SymNet systems. Symetrix has been involved in many designs where the LEDs for the ARC-SWK (or ARC-SW4) need to respond in a unique fashion in relation to the buttons they are associated with. In standard modes, the LEDs follow the buttons and will light green or red when the button is pressed or it can toggle on and off when the button is repeatedly pressed.

But what if you want to make the LEDs toggle between green and red? Or what about amber LED indication which can be achieved if the LED red and green state are triggered simultaneously? To achieve this, you have to be aware of a few things…

In the Controller Manager, create an ARC-SWK in the RS-485 Network.

Double-click the ARC-SWK in the menu tree to edit its settings and select the “Switches Tab”.

Fig 1: Controller Manager Window (under the Tools pull-down menu)

Select “Independent Switches” mode in the Switches tab.

Fig 2: Independent Switches Mode

Select “Manually Assign LEDs” in the “Switch LEDs” mode. Now the LED Number pull-down will be activated and you can select each LED for editing. The “Controller Number” assignments for the Green and the Red LEDs can now be set.

Fig 3: Manually Assign LED mode

The Next phase uses the RS-232/485 Output modules. These are located in the Control Modules menu in the SymNet Toolkit (F8 toggles the toolkit on and off).

Fig 4: RS-232/485 Output Module located in: Control Modules> Control Outputs> RS-232/485 Output module

Now let’s look at a design concept where 2 presets are toggled on and off with one button on an ARC wall panel. Below is the module design.
View Image

There is a button that would be linked to the button on the ARC SWK.

There are 2 preset trigger modules and an inverter.

The inverter module allows one preset to be triggered when the button is pressed/on and another when the button is pressed/off.

The RS-232 modules are then used to relay controller number information to the RS-485. Notice they are set to numbers 1 and 2.

These are the same setting as in Fig 3 which shows how the ARC needs to be configured.

Remember the ARC entire site file needs to be downloaded before it will work. The ARC network has a separate download.

The distance varies greatly depending on the type of ARC, the gauge of the cable, and the number of arcs chained together.  Download Link: ARC Power Calculator.

ARCs are extremely flexible and can be assigned virtually any real-time parameters depending on what host DSP it is controlling.  Generally ARCs are used for volumes, buttons, and presets.

ARC firmware is managed in Designer in the Controller Manager.

Tools > Controller Manager.