Daisy 9017, Руководство пользователя

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Model 9017 Y/Z-Purge Operator Interface Daisy Data Displays, Inc.
February 2022 10 D011-000002
6 Operation Notes
6.1 Division 1 Z-Purge
When using a Z-purge system, it is the operator’s responsibility to disconnect power
and signal paths in the event of a purge failure (that is, if the pressure in the unit falls
below a preset level). Such a failure is indicated by several means. DAISY units are
equipped with both an indicator light (the “Pressure Good” LED shown on drawing
P017) and an internal pressure meter (shown on the same drawing). If the “Pressure
Good” indicator is extinguished, or if the internal pressure meter is in the red zone
below 1” of water column, the operator should immediately disconnect power and
signal connections to the unit using switches in a safe area .
DAISY’s Z-purge systems are also equipped with alarm contacts that switch state
simultaneously with the “Pressure Good” indicator. These can be connected to an
alarm system or supervisory control system to provide further indications to the
operator and/or the supervisory system. The operation of the alarm contacts and the
“Pressure Good” indicator light is detailed in the flowchart shown in Figure 6.1 and in
Table 6.1 on page 10.
Figure 6.1 Z-Purge Alarm Logic
Power Pressure NC1 & NC2 NO1 & NO2 Pressure (LED)
Off < 0.4” W.C. Closed Open Off
Off
> 0.4” W.C.
Closed Open Off
On < 0.4” W.C. Open Closed Off
On > 0.4” W.C. Closed Open On
Table 6.1 Z-Purge Alarm and Indicator States