Honeywell W7752D specifications Occupancy Status

Models: W7752D

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EXCEL 10 FCU CONTROLLER LNS PLUG-INS USER GUIDE

Window Sensor

The digital input for reading input from a window contact provides the Excel 10 FCU Controller with a means to disable its temperature control activities if someone has opened a window or door in the room. If no window sensor is directly connected to the Excel 10 FCU Controller, the sensor from another node may be used by binding it to nviWindow. Frost protection remains active. Normal temperature control resumes when the window closes.

Demand Limit Control

When a high-electrical-demand signal is received from an energy management system via the LONWORKS network (nviDlcShed), the Excel 10 FCU Controller uses Demand Limit Control Bump to shift the current setpoint (down for heating and up for cooling) by the configured value to save energy.

Optimum Start Gradients

There are two parameters, Cool Rec Ramp and Heat Rec Ramp, which can be configured to cause the cooling and heating setpoints respectively to ramp up to their occupied settings from their unoccupied or standby settings prior to scheduled occupancy. The Excel 10 FCU Controller uses the configured rates to determine the optimum time to start increasing the heating or cooling demand. See the following figures. The configuration parameters are in K/hour.

Fig. 5. Optimum start - cooling

Fig. 4. Optimum start - heating

Occupancy Status

The occupancy status is determined based upon the following table. Manual override may come from nviManOccCmd or from the bypass push-button.

 

Table 3. Effective occupancy mode arbitration

scheduled occupancy mode

occupancy sensor status

 

manual override status

"occupied"

room occupied

 

not assigned

"occupied"

room not occupied

 

not assigned

X

X

 

"occupied"

X

X

 

"unoccupied"

X

X

 

"standby"

"occupied"

X

 

"standby"

"standby"

X

 

not assigned

"standby"

X

 

"standby"

"unoccupied"

X

 

not assigned

"unoccupied"

X

 

"standby"

X=Don't care

 

 

 

effective operating mode

OC_OCCUPIED

OC_STANDBY

OC_OCCUPIED

OC_UNOCCUPIED

OC_STANDBY

OC_OCCUPIED

OC_STANDBY

OC_OCCUPIED

OC_UNOCCUPIED

OC_BYPASS

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EN2B-0285GE51 R0909

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Honeywell W7752D specifications Occupancy Status

W7752D specifications

The Honeywell W7752D is a versatile and advanced electronic gas combination control designed primarily for use in commercial heating systems. This product stands out for its ability to manage both gas ignition and safety functions, which are critical for maintaining the efficiency and safety of heating appliances. Its robust construction and advanced features make it a popular choice for HVAC professionals and service technicians.

One of the main features of the W7752D is its integration of multiple functions in a single device. It serves as both an automatic gas ignition control and a safety shut-off valve, which simplifies installation and reduces the need for additional components. This integrated design not only enhances reliability but also streamlines maintenance procedures.

Another notable technology utilized in the W7752D is its microprocessor-based control logic. This advanced technology allows for precise management of the ignition sequence, improving the overall efficiency of the heating system. The microprocessor enables the control to adapt to varying operating conditions, ensuring optimal performance even under changing demands.

The W7752D is equipped with features that enhance user-interface and diagnostics capabilities. It includes LED indicators that provide clear information about the operational status and any potential issues. This diagnostics capability facilitates easier troubleshooting, saving time and reducing the likelihood of extended downtimes.

Safety is a primary concern in gas appliances, and the W7752D addresses this with built-in safety mechanisms, including flame detection technologies. These features ensure that the appliance operates safely, automatically shutting down in case of any irregularities during operation. This emphasis on safety not only protects property but also provides peace of mind for users.

In terms of compatibility, the Honeywell W7752D is designed to work with a wide range of gas heating appliances. Its flexibility allows it to be used in various applications, making it suitable for different types of commercial environments. Additionally, the control complies with relevant safety and performance standards, ensuring reliable operation.

In summary, the Honeywell W7752D combines advanced technology with essential safety features, making it a top choice for commercial heating applications. Its integrated design, microprocessor-based control, user-friendly diagnostics, and robust safety mechanisms make it an essential component for efficient and safe gas heating systems. Whether it is for new installations or replacements, the W7752D provides HVAC professionals with the reliability and ease of use they demand.