Siemens 125-5033 owner manual Emergency Purge Feature, Alarm Strategies, Emergency Purge Operation

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Fume Hood Controller Owner's Manual

Alarm Strategies

One approach is to use the ALARMs to indicate a condition that requires immediate attention and the WARNINGs to indicate a condition that may require attention but is not urgent. In that case, the alarm limits would be set to indicate that it is unsafe to work at the fume hood. The warning limits would be set at a level that is safe, but indicates that the system may not be operating correctly. These values should be selected by the person responsible for laboratory safety.

The delay timer is adjustable and should be selected with safety in mind. Laboratory safety procedures will not be effective if there are numerous nuisance alarms. The delay timer should be set at a sufficiently large interval to prevent nuisance alarms. However, if the delay timer interval is excessively large, there is a risk of having a laboratory worker standing in front of an ineffective fume hood for a prolonged period. The delay timer interval should be selected by the laboratory safety officer with the above considerations in mind.

Emergency Purge Feature

Under certain emergency conditions, such as a spill in the fume hood, it may be necessary to purge the air from the fume hood. The Emergency Purge sequence enables the fume hood user to override normal airflow setpoint and temporarily increase the airflow beyond the value needed to maintain the airflow setpoint.

The Emergency Purge overrides any other control mode in the Fume Hood Controller and has two modes of operation; maximum purge, and controlled purge.

The maximum purge moves the exhaust airflow control device to full open and holds it there regardless of airflow. This mode has the advantage of providing immediate expulsion of the contaminating agent, but may cause airflow problems in the fume hood and reduce the airflow capacity at other fume hoods.

The controlled purge continues to modulate the exhaust airflow control device and controls the airflow, but at a higher than normal level.

The Fume Hood Controller can be set up to purge in either mode or to start in maximum purge and then switch to a controlled purge after an adjustable amount of time.

Emergency Purge Operation

The Emergency Purge sequence is initiated by pressing the Emergency Purge button on the ODP. When the Emergency Purge button is pressed, the fume hood will go to the maximum purge for the time selected in the emergency timer. After the emergency timer elapses, the Fume Hood Controller will begin actively controlling the airflow, but at an increased setpoint. The Emergency Purge sequence is canceled by pressing the Emergency Purge button a second time. The ODP indicates an Emergency Purge sequence in three ways:

•The red LED illuminates.

•The horn sounds.

•EMERGENCY PURGE and EEE display.

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Siemens Building Technologies, Inc.

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Contents Two-State Constant Volume Fume Hood Controller 125-5033 Rev. AA, SeptemberPage Service Statement Page Table of Contents High and Low Exhaust Flow Control Manual Conventions How To Use This ManualManual Organization Convention ExampleNotation Symbol Meaning Manual SymbolsWhere To Send Comments Datamate SoftwareElectronic Actuation Product OverviewRelated Equipment Pneumatic ActuationOrdering Notes Application DescriptionHardware Inputs Power WiringCommunication Wiring Hardware OutputsLED Type Controller LED IndicatorsOperator Display Panel ODP IndicationLaboratory Exhaust Air Terminal Operator Display PanelVenturi Air Valves Laboratory Exhaust Air TerminalHigh Speed Electronic Actuation Low Speed Electronic Actuation Pneumatic ActuationAnalog Output-Pneumatic AO-P Module Pneumatic ActuatorAirflow Sensor Differential Pressure TransmitterCables Fume Hood Controller 2-Position Constant Volume ApplicationsControl Loops High and Low Exhaust Flow ControlCalibration ElectronicAlarm Operation DO3 Output FunctionalityAlarm Strategies Emergency Purge FeatureEmergency Purge Operation Emergency Purge Strategies Fail-safe Operation Point Database Address Descriptor DescriptionFlow Coeff Flow P Gain Basic Service Information TroubleshootingPreventive Maintenance Safety Features Controller LEDsCentralized control GlossaryAlgorithm Control loopEquipment controller OCC modeEnglish units Field panelOn text Override switchSlave mode Portable Operator’s TerminalUnocc mode Terminal Equipment ControllerIndex ApplicationIndex

125-5033 specifications

The Siemens 125-5033 is a highly regarded circuit breaker in the world of electrical engineering and power distribution. Known for its robust design and versatile applications, this device offers a host of features that make it suitable for both commercial and industrial use.

One of the main features of the Siemens 125-5033 is its compact size. This allows for easy integration into existing systems without occupying excessive space, making it an ideal choice for facilities with limited room for electrical infrastructure. Its ability to handle high current ratings, typically around 125 amps, ensures that it can support a variety of electrical loads, making it versatile across different applications.

The Siemens 125-5033 employs advanced technologies, such as thermal-magnetic trip mechanisms. This allows for reliable protection against overloads and short circuits. The thermal component of the trip mechanism is designed to react to sustained overcurrent conditions, while the magnetic component responds instantaneously to short circuits. This dual-functionality ensures that the circuit breaker can effectively protect both the conductors and the connected equipment.

In terms of safety, the Siemens 125-5033 comes with advanced arc suppression technologies that minimize the risk of arcing during the circuit interrupting process. This not only enhances the longevity of the breaker but also safeguards personnel working near electrical installations. Additionally, the device features a clear, accessible reset mechanism, making it user-friendly and easy to operate in case of an interruption.

Another notable characteristic of the Siemens 125-5033 is its built-in ground fault protection option. This capability provides an added layer of safety, ensuring that any ground faults are detected and addressed promptly. It is particularly useful in environments where moisture or dust can compromise electrical safety.

The Siemens 125-5033 also boasts compatibility with various monitoring and control systems, enabling seamless communication and integration into smart building management systems. This feature allows facility managers to monitor power usage, identify potential issues, and optimize energy consumption effectively.

Overall, the Siemens 125-5033 circuit breaker is a reliable, safe, and technically advanced choice for those looking to enhance their electrical systems. Its compact size, dual-trip mechanism, ground fault protection, and compatibility with modern technologies make it a valuable asset for any facility looking to improve its electrical safety and efficiency.
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