Installation
Through-Hole Installation¶
The Veva III is designed to be mounted using its single through-hole design using a 5/16" (M8) bolt or ⅜" (M10) in the Veva III - 03 and later models.
Drill a hole in the target surface. The diameter of the hole should be in accordance with the specification of the 5/16" (M8) bolt. Generally, this would be a hole large enough to accommodate an anchor.
- Make sure there is a metal washer under the head or nut to prevent the nut from coming into direct contact with the housing.
Securing the Veva III
If you're concerned about theft, we suggest two approaches to protect your device.
- Use a security bolt when attaching the Veva III to a surface. Bryce Fastener manufacturers fasteners with unique drive heads. When using a security fastener, don't use permanent fasteners!
- Use an outer enclosure around the Veva III. In many situations, the Veva III can communicate through a fiberglass enclosure, but if you choose a metal enclosure, be sure to place the antenna outside the enclosure and attach to the Veva III using a thruhole.
Orientation¶
The Veva III can be mounted either horizontally or vertically without having to reconfigure the vibration transducers.
Ground and Buried Installations¶
The Veva III is designed to meet IP67 specification and can be placed on the ground or buried.
For ground installations, it's common to place a sandbag on top of the device. Please use caution so the antenna isn't covered by the sandbag or any weight of the sandbag resting on the antenna.
For ground and buried applications, we recommend placing the device inside a plastic bag. While this isn't necessary to protect from water intrusion, it does make clean-up after a job much simpler as dirt doesn't get into the crevices or screw caps on the Veva III. We recommend a plastic bag about 10 mil thick. Household freezer bags with a zipper work well for these applications.
Additionally, the antenna should not be buried otherwise communications could be interrupted. We recommend using a coax cable to extend the antenna above ground. Simply mount the antenna to a stake (rebar or metal fence post) next to the device.
Extending the Antenna¶
There are certain cases where the antenna must be extended away from the Veva III for better reception. For example, installing a Veva III in a basement may require the antenna to be extended above grade and outdoors.
Cable thickness, length and construction all play a factor into signal loss. Obviously, the objective is to keep signal loss at a minimum by keeping the cable length as short as possible. When that's not possible, an installation may require a "low loss" type coax cable. Care should be taken to minimize cable loss in ensure reliable communications of the Veva III.
The following on-line resources might help you understand more about coax cable.
- Understanding Coaxial Cables - The Complete Guide by Wilson Amplifiers
- Coaxial Cable Attenuation & Power Handling Calculator by Times Microwave Systems.
Extension Cabling for the Veva III
The Veva III's antenna connector is a reverse polarity SMA connector.
- Coax cables already in your inventory may not fit properly without an adapter similar to this one available from DigiKey. Please note the antenna provided with the Veva III may also require an adapter to be compatible with your cables.
- If you intend to purchase an extension cable compatible with the Veva III without using an adapter, look for cables identified as "RP SMA Male Plug, Female Socket to RP SMA Female Jack, Male Pin." For example, this 3 foot cable is available from DigiKey. Other lengths are available.
- Cables should be 50-ohm characteristic impedance.
- When cable lengths are more than fifteen feet, we recommend using low loss cables, LMR-400 equivalent or better.