IM-P402-129
EMM Issue 7
3
Static precautions (ESD)
Static precautions must be observed at all times to avoid damage to the product.
Level control and level limiting products in steam boilers
Products / systems must be selected, installed, operated, and tested in accordance
with:
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Local or National standards and regulations.
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Guidance Notes, (Health and Safety Executive BG01 and INDG436 in GB).
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The requirements of Approvals Authorities.
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Boiler Inspection Bodies.
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Boiler manufacturer’s specifications.
Two independent low water limiting systems must be installed on steam boilers. Level
probes must be installed in separate protection tubes / chambers, with sufficient
clearance between the tips, and earth.
Each probe must be connected to an independent controller. The alarm relays must
isolate the boiler heat supply at low alarm status.
A high water alarm may be part of the water level control, or a separate system.
An independent high water alarm system must be fitted if it is considered a safety
requirement.
In this case, the relays must simultaneously isolate the feedwater supply and the
boiler heat supply at high alarm status. All boiler water limiters require regular
functional testing.
The level probe and controller is only part of the safety system. To complete the
system, additional circuitry (wiring, relays, alarm bell / lamp etc.) is required.
A suitable water treatment regime must be used to ensure continuous safe and
correct operation of the control and limiter systems. Consult the above authorities
and a competent water treatment company.
Содержание LC1350
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