Frequently Asked Questions - Hood Control Prewires Models SC and DCV

Hood Control Prewires (Electrical Control Packages, or ECP) are commonly specified and included with commercial kitchen ventilation hoods to achieve necessary Sequence of Operation (SOO) function for code compliance, energy savings, and improved indoor air quality.

ECP commonly control the following in a kitchen ventilation system:

-The exhaust fans

-The dedicated make up air fans

-Temperature sensing for compliance with International Mechanical Code regarding automatic activation

-Fan action in the event of fire system activation

-Activation of shunt trip breakers and electrical gas valves in the event of fire system activation.

Prewires have gone through a few generations of technology. All prewires from ~2013 to 2025 utilize the ECPM03 printed circuit board along with one or more HMI screens or face plates. These models are named SC and DCV for standard non-modulating controls and modulating controls respectively.

The following table describes some common terminology and FAQ for ECPM03 based hood control prewires.

Prior prewire types, namely analog controls, EMS, and EMSplus are obsolete and no longer supported.

ECPM03 Based SC / DCV Hood Control Prewires

Question	Answer	Additional Information
What does DCV stand for?	Demand Control Ventilation	Written Spec Link: Specifications
What does SC stand for?	Smart Controls	Smart Controls and DCV utilize the same control circuit board (ECPM03). Reference the DCV Manual for information on SC.
What does HMI stand for and what is it?	HMI stands for Human Machine Interface. The HMI has a centrally located LCD screen with two buttons on each side. This is the "switch plate" used for light control, fan control, programming configuration changes, and other functions depending on how the ECP was ordered/programmed
What is a Supply/MUA Interlock Fault?	The Supply Interlock Fault occurs when there is not continuity between IL1A and IL1B low voltage terminals on the ECPM. The signal is wired through a relay (RE-DV) in the supply fan which energizes when the intake damper end limit switch is made. This is usually caused by incorrect or incomplete wiring between the supply fan and the ECP.	MUA Interlock Fault Troubleshooting Guide
Do I need to install the room temperature Sensor?	Room temperature sensors are necessary for the system to automatically monitor cooking equipment and activate in compliance with the international mechanical code. When using Demand Control Ventilation (DCV), the room temperature sensors enable the system to adjust fan speeds based on temperature variations.	YouTube Video: Temp Sensor Wiring
Where should I install my room temperature sensor?	The room temperature sensor should be installed approximately 6 feet above the floor in order to obtain an accurate reading. The sensor should not be installed on ceiling tiles or above the ceiling. The ideal sensor placement would be similar to the location of a heating/cooling thermostat, not subject to high radiant loads from cooking processes.	YouTube Video: Temp Sensor Wiring
Why is "Temperature Sensor XX Not Connected" displayed on my control panel?	The control panel is programmed for temperature sensors, and it detects when a sensor is not connected or wired in properly. Refer to the wiring diagram on the door of the control panel and make sure all sensors shown are wired in.	YouTube Video: Temp Sensor Wiring
What is the maximum length for CAT-5 cables?	Communication Only (Non-Powered Devices) - VFD, CORE Board, etc. - 1,000 feet. Powered devices - HMI, MSC, etc. - 328 feet.	N/A

EMS (obsolete 2012 and earlier)

Please note, EMS is No Longer Supported (NLS).

Replacement parts are not available.

Consult your local CaptiveAire Sales office for details on updating EMS to current DCV models using an "EMSplus Retrofit Kit"

Question	Answer
What is EMS	EMS, or Energy Management System, is a type of hood control panel produced from the mid 2000s until 2012. EMS was replaced by model DCV.
What is a PXR4 Temperature Controller?	EMS utilized a third party temperature control and measurement device called a PXR4. PXR4 took in reference temperatures and output signals to the prewire to activate fans. With analog controls, these signals would simply activate a starter or contactor. With modulating VFD based controls such as on the EMS, the signal was utilized to modulate the speed of the VFD

EMSplus (obsolete 2012 and earlier)

Please note, EMSplus is No Longer Supported (NLS).

Replacement parts are not available.

Consult your local CaptiveAire Sales office for details on updating EMSplus to current DCV models using an "EMSplus Retrofit Kit"

Question	Answer
What is EMSplus?	EMS plus is an obsolete electrical package that used a touch screen, PLC based logic, and VFD's. This was replaced by DCV.
Why am I getting a VFD Communication Fault?	All VFD's must have P194 set to 225. One or more CAT-5 cables may be faulty.
What is the Setup ID and Password?	ID: setup Password: change
What is the Factory Settings ID and Password?	ID: factory Password: cas
What is the Fire Options ID and Password?	ID: admin Password: casfire
Why can't I access parameter P410?	This means that the VFD is not communicating with the interface module. Many times, when the VFD fails, the interface module fails as well. These should be replaced as a pair. See link for interface module information.
What is the maximum length for CAT-5 cables?	Communication Only (Non-Powered Devices) - VFD, CORE Board, etc. - 1,000 feet Powered devices - HMI, MSC, etc. - 328 feet.