Attachment__5_-_23_09_00_-_Instrumentation_and_Control_for_HVAC.pdf

Silt Pumping Plant Modernization Silt Project - Upper Colorado Region Solicitation No. R16PS00121

Instrumentation And Control For HVAC

23 09 00 - 7

2.13 THERMOSTATS

A. Line-Voltage, On-Off Thermostats: Bimetal-actuated, open contact or bellows-actuated, enclosed, snap-switch or equivalent solid-state type, with heat anticipator; listed for electrical rating; with concealed set-point adjustment, 40 to 85 degrees F set-point range, and 2 degrees F maximum differential.

1. Electric Heating Thermostats: Equip with off position on dial wired to break ungrounded conductors.

2. Selector Switch: Integral, manual on-off-auto.

2.14 ELECTRICAL CONDUITS, TERMINALS, AND WIRING

A. In accordance with Division 26.

2.15 CONTROL CABLE

A. Electronic cables for control wiring:

1. Control devices and panels containing low voltage power sources:

a. Comply with NEC Class 2 requirements (current limiting), or

b. Supplied with branch circuit fusing to limit control circuit current to NEC Class 2.

c. Control transformers:

1) Be of inherent current limiting type, or

2) Installed with primary disconnects and overload protection.

2. Shielded Cable:

a. Use twisted shielded cable where required to properly protect controls from false signals and electrical noise.

b. Shielding shall be fine braided tinned copper (90 percent coverage) or aluminum foil (100 percent coverage).

3. Minimum Requirements:

a. Communication Cable: Twisted shielded pair, 18 gauge.

b. Analog Input: Twisted shielded two, three, or four-wire as required, 18 gauge.

c. Analog Output: Twisted shielded, 18 gauge.

Silt Pumping Plant Modernization Silt Project - Upper Colorado Region Solicitation No. R16PS00121

Instrumentation And Control For HVAC

23 09 00 - 8

PART 3 EXECUTION

3.01 GENERAL

A. System shall be complete, put in operation, tested and calibrated prior to the 2018 irrigation season.

1. Furnish time for adjustments after the installation.

2. Contractor is responsible for providing sequences of operations specified herein or on mechanical drawings even if equipment and controls are provided by others.

3. For sequences specified in other sections, if equipment and controls are provided by others, Contractor shall still be responsible for verifying sequences of controls and coordination.

B. Perform work in accordance with NFPA 70E.

3.02 INSTALLATION

A. Enclosure layout:

1. On face of enclosure panel, provide each ventilation fan with fan circuit breaker and the following devices. Install devices in the listed decreasing sequential order:

a. A three-way HAND-OFF-AUTO switch.

b. A OFF indicating light, color: green.

c. A ON indicating light, color: red.

d. Thermal overload reset button.

2. Provide nameplates for the following:

a. HAND-OFF-AUTO switches.

1) Below the switch, text to read, “HAND-OFF-AUTO” in the order appropriate to switch configuration.

2) Above the switch, text to read, “VENT FAN NO. {INSERT FAN

NUMBER HERE}”.

b. Green indicating lights. Text to read, “OFF”.

c. Red indicating lights. Text to read, “ON”.

d. Thermal overload reset button. Text to read, “OVERLOAD RESET”.

B. Electrical conduits, terminals, and wiring.

1. In accordance with Division 26.

C. Enclosure Fabrication:

1. Mount ground bus at bottom of enclosure. Electrically bond to enclosure.