Invensys wireless tank monitor

Invensys Wireless Tank MonitorRobertshaw (an Invensys company) use custom Taoglas embedded GSM antenna in their Centeron Wireless Tank Monitoring System.

Centeron Wireless Tank Monitoring Systems are designed to help companies that monitor tanks have maximum control over product distribution, collection and overall vessel management. The Centeron System tracks tank levels for you, so you know exactly when and where to make deliveries.

Robertshaw Industrial Products – an Invensys company – measure tank fluid level and transmit that information to a Centeron controller via a robust wireless data link. The Centeron Radar Monitor has excellent accuracy and repeatability. It is used in a wide variety of fluid products and is especially suited for petroleum. Robertshaw had a requirement for Taoglas to design an embedded GSM antenna in each tank monitoring device to allow the devices to communicate with the central systems allowing customers to view and be alerted to the status of fluid levels in their tanks.

Embedded GSM antennas are a challenge due to the effects of the surrounding components, device activity and housing has on the antennaitself. When USA PTCRB and network approvals are required the challenge is increased due to the stringent TRP/TIS requirements (Total Radiated Power/Total Isotropic Sensitivity). Taoglas successfully delivered the solution to Robertshaw and helped them pass the PTCRB approvals.

Only the most experienced antenna designers can successfully bring such antenna designs to completion. There are always issues to be faced along the way and the most important item is open and efficient co-ordination between the antenna designer and customer’s engineering team so as not to delay the overall product roll-out.

So Taoglas’ senior antenna engineer at our US product development centre based in San Diego stepped in and reviewed the original area set aside for the antenna. Different antenna design options were discussed with Robert Shaw in the form of a feasibility report.

Eventually a simple FR4 dipole antenna design was chosen. This may be considered a simple design, however to achieve over 50% efficiency is never a simple task for any GSM antenna. Achieving over 50% efficiency at each band is Taoglas target for custom internal GSM antennas.

Special attention was taken with cable routing to achieve the desired efficiency targets for PTCRB approval. A ferrite core was added to damp down system noise. The project design lasted a total of 3 months.

Taoglas helped Robertshaw on final PTCRB approval issues with the device. Taoglas can also be a one-stop for our customers, from antenna and device evaluation through to design and into production delivery. Production is carried out in Taiwan by Taoglas at advanced manufacturing facilities.

All antennas are 100% tested with network analyzers prior to shipping to meet the stringent return loss specifications. Each cable is tested for pull strength to ensure mechanical connection is solid. As can be viewed at the device website, centeron, the product is shipping successfully.