CleaverBrooks ADAC 1000, Руководство по эксплуатации

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Chapter 3 — Commissioning
Part No. 750-386 3-37
3.22-DA Bypass
For dual tank systems only; this feature allows the DA to be
bypassed for maintenance or inspection. In DA Bypass mode the
boiler feed pumps draw water directly from the surge tank.
A Normal – Bypass selector switch and corresponding Low Water
Cutoff wiring of the control panel is required for the DA Bypass
function to operate correctly. All valving to allow the feed pumps to
draw water from the surge tank is manual.
In DA Bypass Mode, the Transfer Pumps are disabled from starting
automatically. The Surge Low Water Cutoff must be wired according
to the wiring diagram to allow the Boiler Feed Pumps to be disabled
should a Surge Tank Low Water Cutoff condition occur while in DA
Bypass mode.
If the Feed Pump Auto Restart Pump feature is enabled, the Transfer
Pump Auto-Restart Level and Surge Tank Low Water Cutoff levels
are used to start and stop the feed pumps, based on the water level
in the surge tank.
DA Bypass can operate with or without a Surge Primary Makeup
Valve.
3.22.1 - DA Bypass - No Surge Primary MUV
The DA Secondary Makeup Valve is required and is used to provide
makeup water to the Surge Tank in DA Bypass mode. The DA
Secondary Makeup Valve will modulate based on Surge level not DA
level. This makeup valve must be configured in both Normal
operating mode and in DA Bypass mode.
From the HMI Main Screen either the “DA Second Makeup Valve”
or “DA Second MUV DA Bypass” pushbutton will be enabled and
the other pushbutton disabled and grayed out depending on which
mode is active.
To allow the DA Secondary Makeup Valve to provide water to the
Surge Tank, in DA Bypass mode, additional valving and piping is
required. All valving is manual. The DA Primary MUV is
automatically placed in Manual Mode and Closed when switched to
DA Bypass. Switching to Normal operating mode the DA Primary
MUV is automatically switched to Auto Mode and will begin to
modulate based on DA Tank level.