Most Popular Articles
Remote Site Control
Find the fit for the functionality you need with a plethora of choices
Like all remote control devices in this category, all the inputs, outputs and status connections need to be broken out from their multiple-circuit connectors. The MAC 216 has quite a few unique features. It has a built-in PSTN dial-tone detector. It's nice to know ahead of time if your phone line to the unit is dead (although you'll have to be informed via IP in some fashion). It logs caller-ID on incoming calls. (Who was it that just turned the transmitter off?) It has 16 different call-out lists, which is handy because you might want the unit to call a PD directly for a dead-air status alarm. Not everyone on the call-out list has to deal with every type of status alarm then.
MacComm is the software used on the device, and it has four primary features. First, it allows users to configure what Davicom calls workspaces, which allows the user to make up a one-line diagram of the broadcast system being controlled by the unit. It allows for the creation of complex operations by means of virtual logic gates, mathematical functions, qualifiers and inverters. It allows the user to look at telemetry in a graphical form; and finally, it allows the user to see trends in telemetry by means of graphs.
Another player in the remote control space is Statmon. While the company offers an extensive product line, the system I'll focus on is Axess. This system is different than what we've typically used over the years because it isn't a stand-alone box that we think of as a remote control. This is a system that is assembled, and consists of the computer, the Axess software, and the interface known as the GPX-32. A basic remote control system has 32 optically isolated status inputs (either polarity available, 88-264Vac input or 18-60Vdc input), 32 balanced metering inputs (100k ohms, ±5Vdc or ±15Vdc, 16-bit ADC) and 32 relay outputs. The opto-isolated outputs, relays and metering inputs accessed via a PDP (punch-down panel), which consists of Krone blocks mounted on a 2RU panel. The PDP connects to the GPX-32, which occupies 1RU.
POTS accessibility is via a modem attached to computer running Axess software. Serial ports can be used for communications between Axess and other devices. The CPU and GPX-32 communicate via Ethernet. The unti provides HTTP, SMTP, SNMP and NTP support. Each remote user is assigned level of control based on his password. The current version of Axess will run on Windows 7 Pro, Windows Server 2003 or Windows Server 2008 R2 32/64-bit.
Aside from using a computer to look at all the various pieces of information supplied by the GPX-32, you can use what Statmon calls OVI (Operator Visual Interface) to build a GUI that shows (for example) signal or data flow, equipment layout, or facility parameters such as ac line voltage, room temperature or door alarms. A video camera can also be accessed as an object in OVI. You can build an OVI template, and copy it, then paste it to another site. In addition to OVI, Statmon provides the Statmon Control Language that allows the user to build scripts so that Axess will perform user-defined actions, based upon input status, metering, and control.
The Worldcast Systems Audemat remote control product is known as Relio. (The particular device I will discuss is actually manufactured by SeaLevel; Audemat makes its own versions known as Relio Silver, along with Relio-mini.) It's a stand-alone unit that occupie 1RU. All the inputs/outputs are brought to multiple-circuit connectors on the rear panel. There are 64 relay outputs (using two separate relay panels, 2RU each), 64 status inputs (using two separate status panels, 1RU each), and 24 analog inputs (1RU panel) with a 14-bit, ±10Vdc input range. Two Ethernet ports, five serial ports (four for RS-232 or RS-485; one for RS-232 only) and four USB ports provide connectivity. A built-in POTS modem with programmable call-out responds to DTMF tones. The unit supports HTTP, SNMP, SMTP and NTP. It uses a Linux-based operating system, Compact Flash storage and a hard drive to store logs.
Like the other units mentioned previously, Relio is a stand-alone unit that lives at the site to be controlled. Even though it supports HTTP, the normal GUI used is called MasterView, and that lives on a computer in the control location. To have access to the Relio at the remote site, you need to place a computer there running MasterView. Configuring of the device is done via software (written by Audemat) known as ScriptEasy. Scripteasy also allows the user to develop scripts, based on objects such as analog inputs, status inputs, relay outputs and other logic operators, so that the device will carry out pre-programmed events. Audemat also has developed two APIs (Advanced Programming Interface) so that Relio can communicate directly (via serial ports) with the Harris Z-series transmitters and the Nautel NV series.
- continued on page 3
Acceptable Use Policy blog comments powered by Disqus
[an error occurred while processing this directive]
Today in Radio History
The history of radio broadcasting extends beyond the work of a few famous inventors.
Read each issue online in our Digital Edition Format in your Web browser.
EAS Information More on EAS
The feed provides feeds for all US states and territories.
Need a calendar for your computer desktop? Use one of ours.
Information from manufacturers and associations about industry news, products, technology and business announcements.
Browse Back Issues[an error occurred while processing this directive]
Also in the January Issue
- Trends in Technology: AES-X210, The "Missing Piece" of AES67?
- FCC Proposes Online Publc File Rules for Radio
- RF Engineering: Licensing AM Stations Using Method of Moments
- Field Report: Zoom H6