Hamworthy Sherborne Series, Installation, Commissioning And Servicing Instructions

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HAMWORTHY HEATING LTD
36
SHERBORNE 500001167/E
APPENDIX B - ELECTRICAL CONNECTIONS & CONTROLS
B1.1 Electrical Supply
IMPORTANT: Individual boiler modules must be earthed.
The boiler must be isolated from the mains electricity supply in the event of electric arc
welding being carried out on any connecting pipework.
1. Wiring external to the boiler must be installed in accordance with the IEE Regulations & any local regulations
which apply. Wiring must be completed in heat resistant 3-core cable of 1.0mm² cross sectional area. Boilers are
normally supplied for connection to a 230 volts, 50Hz mains supply. The LMU control is supplied with a
replaceable fuse (T6.3A). External fuses should be 10A for all boiler modules.
2. 3-Phase Electrical Supplies. Individual modules of Sherborne boilers & boilers installed in close proximity to
each other
MUST NOT be supplied from different phases of a 3 phase supply. The method of connection to the
mains electricity supply must facilitate complete electrical isolation of the single boiler / battery with a separation of
at least 3mm in all poles.
3. A mains isolator must be provided adjacent to the boiler in a readily accessible position. The supply should only
serve the boiler.
4. Volt free contact electrical supplies must be isolatable where fitted.
5. Further details regarding connection to the electricity supply are given in BS EN 60335, Part 1 or BS 3456, Part
201.
6. Refer to figure B1.2 for typical control wiring schematics for multiple boilers.
WARNING: THE MAINS POWER SUPPLY MUST NOT BE SWITCHED
BY A TIME-CLOCK CONTROL.
CAUTION: DO NOT FEED MAINS VOLTAGE ONTO THE TIMER TERMINALS
6. The mains power supply must be maintained at all times. Each Sherborne boiler module incorporates a remote
stop/start loop, which can be used to operate the boiler(s) under a timed regime. The boiler controls provide a 24V
DC signal that can be fed through a volt free contact for operation. Refer to BS 6644 for further information on
installing the electrical supply.
NOTE: FOR BASIC TERMINATION DIAGRAM SEE FIGURE 4.5
ELECTRICAL DATA
Model
Sherborne
SE64he
Sherborne
SE71c
Normal Supply Voltage 230V ~ 50Hz
Power Consumption (maximum) - W 175 175
Start & Run Current (per module) - A <1.0A