Project Number: 228730 WWTE SCADA Upgrades
Issue Date: August 2017 Nashua, NH
J.
The number of conductors shown on the Drawings is not necessarily the correct
number required. As many conductors as are required in each case shall be
installed. In general, grounding conductors are not scheduled.
In general, wiring for the following systems shall be installed in separate conduits.
Do not mix categories in a single raceway.
1. 120 volt power wiring.
2. 120 volt control wiring, including, digital input and output signals.
3. 24 volt DC control wiring, including, digital input and output signals.
4. 24 volt DC analog control wiring (4-20mA).
5. Communications wiring.
6. Special & Emergency Systems
3.02 FIELD QUALITY CONTROL
A.
The Contractor shall test each electrical circuit after permanent cables are in place
with terminators installed, but before cable or wire is connected to equipment or
devices to demonstrate that each circuit is free from improper grounds and short
circuits.
The Contractor shall Megger Test, the insulation resistance between phases and
from each phase to ground for each of the following feeder and motor branch
circuits:
1. Secondary Service Entrance
2. Electrical Distribution Equipment (Main Circuit Breaker, Motor Control
Center, Panelboards, etc.)
3. Transformers
4. Motors
All Megger testing shall be provided to the Engineer.
Measure the insulation resistance with a digital "Megger" insulation testing
instrument in accordance with manufacturer’s recommendations. All test
instruments are to be provided by the Contractor.
If any insulation resistance measures less than 50 megohms, the cable shall be
considered faulty with the cable failing the insulation test. In moist environments,
bag the ends of the cable to prevent a faulty Megger test.
LOW-VOLTAGE ELECTRICAL POWER CONDUCTORS AND CABLES
WOODARD & CURRAN 26 05 19-5
