Frequently Asked Questions

Below is a listing of frequently asked questions about VIVISUN and NEXSYS products. If you have additional questions not covered, please e-mail us your question on the Contact Us page or call Customer Service at (888) 848-4786

Yes, in most instances The VIVISUN LED .75” (19mm) switch is a Fit, Form and Function replacement, for the VIVISUN 95 incandescent. The VIVISUN LED has significant advantages over the incandescent lighting as it requires 1/3 less power and operates maintenance free with well over 100,000 hours reliability. The switch body portion of the VIVISUN 95 incandescent and the VIVISUN LED are the same MIL-PRF-22885/108 qualified switch body and are fully interchangeable.

Upgrades to LED lighting should be made to all units on a panel and mixing LED and incandescent lighting on the same panel is not recommended. Some minor lighting difference is typical but the color, appearance and brightness are very similar. The LED responds with a uniform voltage dimming curve similar to typical incandescent performance. In certain applications the LED may exhibit higher brightness levels at full rated voltage than older incandescent lamps.

In order to further simply the use of LED lighting, the VIVISUN .75” (19mm LED) has multiple dimming options. The primary dimming option as referenced is voltage control and the LED follows a similar curve to incandescent lighting. The LED may also be dimmed with discrete inputs (Discrete Dimming Data Sheet) to match predetermined brightness levels. Resistance dimming is also an option but the LED draws 1/3 less current and will appear brighter than incandescent lamps at the same resistance setting.

When converting to the LED it is also necessary to determine polarity for illumination. The polarity is specified as either common anode (current sinking) or common cathode (current sourcing).

To specify the VIVISUN LED refer to the Part Configurator

No, the VIVISUN LED cap assembly is a sealed integrated unit that must be replaced as an assembly. It contains four independent lighting quadrants. A lighting quadrant’s electronic circuit contains four LEDs for the .75” (19mm) unit or 6 LEDs for the 1.40” (35.6mm) rectangular unit. Each cap also contains a layered fault tolerant assembly with an independent Driving, Dimming and Protection Circuit (DDPC). In the unlikely event of an LED failure, a quadrant would lose lighting from only two LEDs and continue to maintain legend readability even in a failure mode.

The power consumption of the .75” (19mm) LED is 1.18 watts at 28 VDC, drawing .042 amps of current. The power consumption for the 1.40” (35.6mm) rectangular LED is 1.5 watts at 28 VDC, drawing .064 amps of current.

No, the VIVISUN switch is not typically a repairable assembly. However, the switch assembly is comprised of two subassembly components that may be replaced should they be damaged. The two subassemblies are a separable illuminated cap and a switch body and these components may be purchased separately. The Part Configurator offers an option to specify the cap or body part number or please contact Applied Avionics for assistance.

It is possible in certain cases to have a new VIVISUN Switch assembly reworked. Considerations such as changing the color of a legend, LED polarity or the switch action are examples of items that may be reworked. Please contact the Applied Avionics Technical Sales Support Team for assistance and to receive an RMA authorization.

NVIS compatible lighting is an option available on each of the VIVISUN LED switches. The option is specified in the part number definition and allows an operator to use Night Vision Goggles with no interference in the goggles when the switch is illuminated. VIVISUN NVIS lighting is compliant with MIL-STD-3009 and RTCA/DO-275 which defines colors, brightness levels, and spectral radiance. The website Part Configurator provides a step by step process for specifying an NVIS compliant part number.

The current version of the SR429 can accommodate one ARINC input and can be configured to receive a single data label (ie 000-377) and associated data bits. Pre-configured units have the label set at the factory; Universal units are able to have the label set and reset after the unit leaves the factory.

No. In order to keep the height of the SR429 as slim as possible, the industry standard 37 pin 2 row D-sub connector was selected.

NEXSYS offers an M81714/5-5 Type 1 rail that can hold 3 NEXSYS Modules. Since each individual NEXSYS Module can hold up to four 4-pin NEXSYS Components or up to two 8-pin NEXSYS Components, a rail with 3 NEXSYS Modules can contain a wide range of mix-and-match NEXSYS Components. Type 1 rails with additional capacity are available from traditional avionics accessory sources.

NEXSYS products provide several relay-replacement solutions for use in signal-level applications. The output load capacity of NEXSYS Component Technology varies by product, ranges between .25A - 2A and should be specified based upon the application requirements. For example, instead of using an external dropout relay, a .25A SSR2H (NC) can be integrated inside of a VIVISUN LED indicator body, perform the dropout function and energize the LED indicator light. The SSR2H is well suited for this type of an application since it sinks more than enough current to energize several VIVISUN LED indicators. Other NEXSYS products like the Electronic Latch, Pushbutton Rotary and Pulse Timer have an output load capacity of 2A (resistive) which is more than enough current to drive many types of aircraft systems.