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| INSTALLATION MANUAL for CFEWH SERIES 6-13 | V01 - 12 / 02 / 2021
ELECTRICAL INSTALLATION
In accordance with the wiring rules, National Electrical Code (NEC), or
NFPA 70, the Live / Live / Ground electrical supply connections Live (L1),
Live (L2) and Ground (Earth ) (LLG) must be permanently connected
to the
14
Terminal Block mounted on the PCBA as shown (see Fig. 1).
Electrical connections should be made as instructed, using appropriate
UL listed strain relief devices.
As per National Electrical Code (NEC), the current in a circuit must not
exceed the current rating of the circuit protective device and this, in turn,
must not exceed the current carrying capacity of the circuit conductors.
Necessarily in this context, both Diversity Factor and Demand Factor
should be taken into account when calculating the electrical load on the
electrical supply.
NATIONAL ELECTRICAL CODE (NEC): ARTICLE 220
BRANCH-CIRCUIT, FEEDER, AND SERVICE LOAD CALCULATIONS
220.1 Scope. This article provides requirements for calculating branch-
circuit, feeder, and service loads. Part I provides general requirements
for calculation methods. Part II provides calculation methods for branch-
circuit loads. Parts III and IV provide calculation methods for feeder and
service loads. Part V provides calculation methods for farm loads.
DIVERSITY FACTOR
Diversity Factor is the ratio of the sum of the individual maximum
demands of the various subdivisions of a system (or part of a system) to
the maximum demand of the whole system (or part of the system) under
consideration. Diversity is usually more than one.
Diversity Factor = sum of total demands ÷ maximum demand on feeder.
DEMAND FACTOR
Demand Factor is the ratio of the sum of the maximum demand of a system (or part of a system) to the total connected load
on the system (or part of the system) under consideration. Demand Factor is always less than one.
Although feeder conductors should have an ampacity sufficient to carry the load, the ampacity needs not always be equal to
the total of all loads on connected branch-circuits.
A study of the National Electrical Code (NEC) will show that a Demand Factor may be applied to the total load. The Demand
Factor permits a feeder ampacity to be less than 100 percent of all the branch-circuit loads connected to it.
IMPORTANT:
This unit is classified as a Class I Bare
Element Water Heater. The appliance must be correctly
connected to the mains earth.
In order to prevent a hazardous circumstance occurring due
to the inadvertent resetting of the thermal cutout, the electrical
supply to this appliance must not be supplied through an
external switching device, such as a timer – nor can it be
connected to a circuit that is regularly switched on and off by
the electricity supply utility.
220-240 VAC
( L / L / GND )
2 POLE CIRCUIT
BREAKER
2P CB P1
2P CB P2
LIVE
|
L1
LIVE
|
L2
EARTH
|
L1
L2
FOR LICENSED ELECTRICIANS ONLY
PAGE 1 of 3
PRELIMINARY INFORMATION
AFTER DIVERSITY MAXIMUM DEMAND
PART II BRANCH-CIRCUIT LOAD CALCULATIONS
PART I GENERAL
220.61
NEUTRAL
LOADS
PART V FARM LOAD CALCULATIONS
PART IV
OPTIONAL FEEDER
AND SERVICE LOAD
CALCULATIONS
PART III
FEEDER AND
SERVICE LOAD
CALCULATIONS
FARM DWELLINGS
ONLY
FARM DWELLINGS
ONLY
Fig. 220.1
Branch-Circuit, Feeder, and Service Load
Calculation Methods
Fig. 1
Electrical Connection Diagram
