Digital Output Modules Each TMR digital output module has three sets of isolated electronics, called channels, which independently accept data from the MP associated with each channel. These channels use a patented Quad Voter circuit to vote a single output signal applied to the load. This voter circuit is based on parallel series paths if two of the three switches (channels A and B, or channels B and C, or channels A and C) command them to close. Quad Voter circuits feature multiple redundancy on all critical signal paths, ensuring safety and maximum availability. For each point, the DO module periodically executes an Output Voter Diagnostics (OVD) routine. For unrestricted safe operation in a variety of multi-fault situations, the OVD detects and alerts on these types of faults: • Spots – Detects all sticking and sticking in less than 500 milliseconds. • Switches – All switches or their associated drive circuits detected on or off. The DO module includes complete, continuous diagnostics for each channel. If the diagnostics detects a fault on any channel, the fault indicator lights up and activates a system alarm. The fault indicator identifies a channel fault, not a complete module fault. DO modules are guaranteed to function properly in the presence of a single fault and can continue to function properly in the presence of some multiple faults. DO modules support hot spare modules. Each DO module is mechanically keyed to prevent improper installation in the configured backplane. • Switches – All switches or their associated drive circuits detected on or off. The DO module includes complete, continuous diagnostics for each channel. If the diagnostics detects a fault on any channel, the fault indicator lights up and activates a system alarm. The fault indicator identifies a channel fault, not a complete module fault. DO modules are guaranteed to function properly in the presence of a single fault and can continue to function properly in the presence of some multiple faults. DO modules support hot spare modules. Each DO module is mechanically keyed to prevent improper installation in the configured backplane. • Switches – All switches or their associated drive circuits detected on or off. The DO module includes complete, continuous diagnostics for each channel. If the diagnostics detects a fault on any channel, the fault indicator lights up and activates a system alarm. The fault indicator identifies a channel fault, not a complete module fault. DO modules are guaranteed to function properly in the presence of a single fault and can continue to function properly in the presence of some multiple faults. DO modules support hot spare modules. Each DO module is mechanically keyed to prevent improper installation in the configured backplane. The fault indicator identifies a channel fault, not a complete module fault. DO modules are guaranteed to function properly in the presence of a single fault and can continue to function properly in the presence of some multiple faults. DO modules support hot spare modules. Each DO module is mechanically keyed to prevent improper installation in the configured backplane. The fault indicator identifies a channel fault, not a complete module fault. DO modules are guaranteed to function properly in the presence of a single fault and can continue to function properly in the presence of some multiple faults. DO modules support hot spare modules. Each DO module is mechanically keyed to prevent improper installation in the configured backplane.
These backplanes can be used with Type 3401 DO modules: • Type 2401 for typical applications. • Model 2401L for low current applications requiring integral current limit. Each output is equipped with a 180 ohm series resistor. • DO External Termination Base for use with Relay Output External Termination Panels in high voltage applications or the Model 9671-610 DO Hazardous Location External Termination Panel.
3401
