Applications

The fume hood operator may silence the horn by pressing the Horn Silence button on the ODP without affecting the Emergency Purge sequence.

In addition to the ODP indicators, the emergency alarm point will toggle to ON and will remain ON until the sequence is canceled. If the emergency alarm is alarmable in the field panel, the condition can be indicated at selected terminals if the APOGEE Automation System is set up for it.

Emergency Purge Strategies

The use of the Emergency Purge button is determined by the work practices established by the laboratory safety officer. As a general rule, there are two groups that should be aware of the use of the Emergency Purge button: the laboratory worker and the laboratory safety officer.

Laboratory worker – In most cases, the laboratory worker uses the Emergency Purge button to increase the fume hood airflow to minimize a dangerous situation.

The Emergency Purge button should not be used as a way to work around the established face velocity and minimum flow setpoints in an effort to make the fume hood "even safer".

Laboratory safety officer – For the safety department personnel to use the Emergency Purge feature effectively, they must select the purge mode that best suits their needs. The selection may be based on knowledge of industrial hygiene, the chemicals used in the laboratory, the organization's emergency procedures, and the capacity of the central exhaust system.

If the maximum purge mode is selected, the emergency timer and the emergency setpoint to their maximum values.

If the controlled purge mode is selected, the emergency timer is set to 0. Select the value for the emergency setpoint to indicate how much you want the emergency airflow to increase over the normal airflow. For example, if your emergency procedures call for closing the fume hood and starting the emergency purge, decide how much airflow you want compared to the minimum airflow. If you want twice as much airflow, set the emergency setpoint to 200%; if you want a 50% increase, set the emergency setpoint to 150%. If you do not intend to have the laboratory worker close the fume hood, then select the face velocity you want the fume hood to control to in an emergency. Compare that value to the normal face velocity setpoint and calculate the emergency setpoint in percent.

NOTE: During a controlled purge, the increased airflow called for in the controlled purge may exceed the range of the flow sensor. If so, the system cannot accurately regulate the airflow and the controller will open the exhaust flow control device 100%.

If a sequence initially employing maximum purge with a switch to controlled purge is desired, set the emergency setpoint as described for the controlled purge. Select a value for the emergency timer to tell the system how long to leave the exhaust flow control device open before switching to controlled purge. Base this on the types of accidents anticipated, the reason you require a maximum purge, and the reason you want to switch it down to a controlled purge.

Siemens Building Technologies, Inc.

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Siemens 125-5033 owner manual Emergency Purge Strategies
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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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