Cold Storage Trim With Automatic Pressure Control System; Supervisory Pressure Switch (Ps-40) - Viking ESFR Technical Data Manual

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The Viking Corporation, 210 N Industrial Park Road, Hastings MI 49058
Telephone: 269-945-9501 Technical Services 877-384-5464 Fax: 269-945-4495 Email: techsvcs@vikingcorp.com
A. Cold Storage Trim with Automatic Pressure Control System
In cold storage areas where temperatures can fluctuate, over-pressurization of the system can
occur. The Automatic Pressure Control System (APCS) is used to prevent this from occurring.
The pressure relief valve (PRV) operates when the set point of 205 PSI (14.1 Bar) is reached.
Normal operation of the PRV includes operation at 90-105% of the set point and closing at 80%
of the set point. The Automatic Pressure Control System (APCS) is designed to maintain a safe
operating pressure below the set point of the PRV and above the maximum residual or static
pressure of water supply system or maximum set pressure of the system pressure switch.
The Automatic Pressure Control Trim is included with the Easy Riser
installed on the primary Easy Riser
The APCS includes an electronic digital pressure switch that includes a normally open SPST
switch that is set to close at a pressure below the PRV set point and open above the static
water supply or shut-off pressure of the riser system. A waterflow switch is to be installed on
the non-interruptible alarm port of the conventional trim on the deluge valve. A normally closed
solenoid valve is to be installed on the cold storage trim at the ¼" connection provided. A 115-
220 VAC, (50 or 60 Hz) GFI protected electrical power supply is to be provided directly to the
switch.
During normal operating condition, the propylene glycol within the system piping network is
pressurized to 50 PSI (3.45 Bar). The APCS uses a digital pressure switch (Switch #4) in
conjunction with a 120 VAC solenoid (Switch #2) to relieve pressure from the system when
the pressure exceeds 85 PSI (5.86 Bar). The digital pressure switch (#4) comes factory set to
operate and energize the solenoid (#2) at 85 PSI (5.86 Bar). The digital pressure switch will
change state and remove power from the solenoid (#2) at 75 PSI (5.17 Bar).
The digital pressure switch (#4) and solenoid (#2) are wired and powered from a dedicated
115-220 VAC (50 or 60 Hz) GFI protected power supply and routed through a water flow pres-
sure switch (#2) as shown in Figure 39. These devices operate independently and are not
connected to either the release control panel or the CS-1 tank and pump unit. The normally
closed water flow pressure switch prevents the APCS from operating under normal water flow
conditions.
The pressure switch on the deluge valve will make the APCS inoperable when the detection
system causes the deluge valve to open. This prevents water flow from the APCS.

1. Supervisory Pressure Switch (PS-40)

The Automatic Pressure Control System includes a
PS-40 Supervisory Pressure Switch that is installed
on the primary Easy Riser
the appropriate supervisory circuit on the Viking VFR-
400 to annunciate a supervisory signal upon a low
pressure condition with the propylene glycol. It is
recommended to set the switch to activate at 30 PSI
(2.07 Bar).
TECHNICAL DATA
®
Check Valve.
® Check Valve and wired to
March 7, 2008
ESFR PRE-PRIMED SINGLE
INTERLOCK PREACTION
COLD STORAGE SYSTEM
®
Cold Storage Trim and