User guide

10
ELECTRICAL DATA
GENERAL
Check the water heater model and rating plate information against
the characteristics of the branch circuit electrical supply. Do not
connect the heater to an improper source of electricity.
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of the model and rating plate marking for satisfactory operation.
Do NOT energize the branch circuit for any reason before the water
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elements to fail.
The installation must conform to these instructions and the local
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connected to the water heater must also conform to the National
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BRANCH CIRCUIT
The branch circuit wire size should be established through reference
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sources in conjunction with the water heater amperage rating.. Wire
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size tables from the Code are reproduced in Table 3. It is suggested
the electrician size the branch circuit at 125 percent of the heater
rating and further increase wire size as necessary to compensate
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the water heater.
HEATER CIRCUITS
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and rating plate provides heater circuit ratings. There are two main
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&RQWURO &LUFXLW Power supply for the electromagnetic
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this manual.
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carries the heating element load.
The following section and pages describe the water heater circuits
and includes wiring diagrams.
CONTROL CIRCUITS
The water heater is equipped with an electronic control system.
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temperature probe with ECO for temperature sensing and limiting, a
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and element current sensors for monitoring the power circuits. Refer
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Sequence of Operation
1. When the control is powered, the UIM should display model
information, water temperature, operating setpoint, heating
status and operating mode.
2. If the control determines that the actual water temperature inside
the tank is below the programmed operating setpoint minus the
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programmed differential setpoints for each heating element.
4. The control remains in the heating mode until the water
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this point the contactors will be de-energized.
5. The control system now enters the standby operating mode
while continuing to monitor the water temperature and the state
of other system devices. If the water temperature drops below
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setpoint, the control will automatically return to step 2 and repeat
the heating cycle.
POWER CIRCUIT
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105°C, sized as necessary.
The following wiring diagrams are included in this manual to show
typical arrangements of electrical components in the control and
power circuits by voltage and phase characteristics. They are to be
used as a reference by the installer or servicer in performing their
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the heater.