Siemens BACnet Heat Pump Controller - Multi-Stage Owner’s Manual

Power Failure Recovery

Upon return from a power failure, the heating and cooling compressors are kept off, the electric heat (if used) is kept off and the fan is kept off. In addition to the equipment being OFF, both cooling and heating loops are set to 0. This situation will remain in effect until the power failure recovery period for this controller is over.

The controller returns to normal control when its power failure recovery period is over. The power failure recovery time for a heat pump is based on the following formula:

RETURN DELAY + (CTLR ADDRESS × 10 seconds)

This lessens the demand of having all the electrical equipment starting at once.

Centralized Alarm Monitoring

DI 6 can be used to monitor an input that changes state when the heat pump is in alarm.

DI 6 can be unbundled to send alarm information to the field panel for centralized alarm monitoring.

Overriding DOs

Heat Pump applications allow spare DOs, damper (DO1 and DO2) and electric heat stages (DO3, DO6 and DO7 when applicable) to be commanded.

Physical points DO1 and DO2 can never be overridden when configured for motor control. However, the position of the attached motor is always commandable via the DMPR COMD point.

To prevent damage to the mechanical equipment, the fan, reversing valve, and compressor(s) DOs cannot be directly commanded ON or OFF unless the point HP DO OVRD is set to ENABLE. When HP DO OVRD is set to DISABL (default), commands to the fan, reversing valve and compressor DO points are ignored regardless of BACnet command priority.

CAUTION:

HP DO OVRD should be set to ENABLE only when there is a complete understanding of the consequences. Since the direct control will override the application minimum on/off time safeties, improper use of DO commands can cause permanent equipment damage. Also, during normal daily operation the override of critical DOs should only be done via a BACnet command.

Fail-safe Operation

If the RTS or the setpoint dial fails, the controller operates using the last known temperature value.

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Siemens 125-699 owner manual Power Failure Recovery, Centralized Alarm Monitoring, Overriding DOs, Fail-safe Operation
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125-699 specifications

The Siemens 125-699 is a state-of-the-art industrial control product that showcases Siemens’ commitment to innovation and quality in automation technology. This device is specifically designed for various industrial applications, providing exceptional performance and reliability.

One of the main features of the Siemens 125-699 is its robust processing capabilities. Equipped with a high-speed processor, it can handle complex control tasks efficiently, ensuring smooth operation even under demanding conditions. This makes it suitable for a wide range of applications, from manufacturing to process automation.

The device supports multiple communication protocols, which enhances its versatility. It is compatible with popular industrial communication standards such as Profinet, Profibus, and Ethernet/IP. This flexibility allows for seamless integration into existing systems and facilitates communication between various devices on the network, making it an ideal solution for modern interconnected factories.

In terms of user interface, the Siemens 125-699 offers an intuitive design with a user-friendly programming environment. The platform supports advanced programming languages, including Ladder Logic and Structured Text, enabling engineers to develop and modify control algorithms with ease. This capability not only improves efficiency but also reduces the time needed for troubleshooting and maintenance.

Another characteristic that sets the Siemens 125-699 apart is its rugged construction. Designed for harsh industrial environments, it features a durable housing that protects against dust, moisture, and extreme temperatures. This robustness ensures longevity and reliability, even in challenging conditions, which is crucial for minimizing downtime and promoting continuous operation.

Additionally, the Siemens 125-699 incorporates advanced diagnostic tools. These tools enable real-time monitoring of the system's performance, allowing operators to detect and address potential issues before they escalate. This proactive approach to maintenance is vital in enhancing productivity and ensuring the smooth operation of industrial processes.

In conclusion, the Siemens 125-699 is a comprehensive solution for industrial automation needs. Its combination of high processing power, versatile communication options, user-friendly interface, rugged design, and advanced diagnostic capabilities makes it a leading choice for companies looking to enhance their automation systems and improve operational efficiency. With Siemens' reputation for quality and innovation, the 125-699 stands as a testament to the company's dedication to advancing industrial technology.
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