Commissioning Instructions

Automatic Demand Shed

Unrestricted

A6V12035398

Automatic Demand Shed

See 2019 nonresidential Compliance Manual section 4.5.1.6 for more information,

section 13.14 NA7.5.10 for acceptance criteria and NRCA-MCH11-A for acceptance

test form. In summary, if this acceptance form is required (box checked on the Title 24

sheet), all controls systems with DDC to the zone level are required to enable

centralized demand shed at non-critical control zones from either a single software or

hardware point in the system.

§120.2(h) Automatic Demand Shed Controls. HVAC systems with DDC to the Zone level shall

be programmed to allow centralized demand shed for non-critical zones as follows:

1. The controls shall have a capability to remotely setup the operating cooling temperature set

points by 4 degrees or more in all non-critical zones on signal from a centralized contact or

software point within an Energy Management Control System (EMCS).

2. The controls shall have a capability to remotely set down the operating heating temperature

set points by 4 degrees or more in all non-critical zones on signal from a centralized contact or

software point within an EMCS.

3. The controls shall have capabilities to remotely reset the temperatures in all non-critical

zones to original operating levels on signal from a centralized contact or software point within an

EMCS.

4. The controls shall be programmed to provide an adjustable rate of change for the tempera-

ture setup and reset.

5. The controls shall have the following features:

A. Disabled. Disabled by authorized facility operators; and

B. Manual control. Manual control by authorized facility operators to allow adjustment of heating

and cooling set points globally from a single point in the EMCS; and

C. Automatic Demand Shed Control. Upon receipt of a demand response signal, the space-

conditioning systems shall conduct a centralized demand shed, as specified

The DXR has a central function that can be used to meet this requirement called

Central Setpoint Shift that is under the Central Operating Mode. In addition,

supervisory PPCL will be required to implement Automatic Demand Shed.