Powerware Digital TV Solutions
Protecting Against Crowbar Events

“Crowbar events” happen inside the inductive output tubes (IOTs) housed in the transmitter. These sensitive, fragile tubes are very expensive, often costing up to $25,000 each. They draw excessive current for operation, which can create a short inside the tube. To protect the tube from being damaged, they have a crowbar circuit to discharge the current in the form of a short.

The transmitter’s crowbar circuit immediately switches off AC power to the amplifier’s high voltage DC power supply when it is fired. At the same time, it places a short circuit (2000–3000 A) on the DC supply to instantly discharge the high voltage filter capacitors.

Powerware delivers:

• Solutions sized to meet the needs of any transmission site, studio or other critical facility
• Optional heavy-duty static switch operation specifically designed to eliminate risks from crowbar events and other transmitter-specific power problems, mitigating the need to over-size the UPS
• Ability to upgrade the UPS to support additional equipment and/or a larger transmitter
• Local, remote and network monitoring capabilities
• Redundancy with Powerware Hot Sync, our patented technology which eliminates a system-level single point-of-failure
• Redundant components within the UPS modules to reduce potential for module failure
• World-class, around-the-clock service by Powerware service personnel with the broadest coverage available in the industry
• 40 years experience in maximizing uptime for critical systems, from 300 VA to >1000 kVA