I INTRODUCTION

The Multiport Electronic Controller (MEC) replaces the SW28 Switchpak, for the Multiport Selector Valve. This service manual is intended to supersede the SW28 Switchpak information in Multiport Selector Valve service manuals.

IIACTUATOR ASSEMBLY

A.MULTIPORT ELECTRONIC CONTROLLER (MEC): SWITCHPAK PEDESTAL, CONNECTOR, SWITCHPAK MODEL SW20N-AM AND ELECTRICAL CONDUIT (OPTIONAL LOCAL CONTROL STATION AND DIGITAL DISPLAY)

NOTE : For MEC, see the typical actuator assembly drawing on page 4.

1.Install Switchpak pedestal (449) in place and install the six studs (452), washers (453) and nuts (454).

2.Start threading the setscrew in the Switchpak connector (457) and place on the speed reducer shaft. Set coupling (455) on top of Switchpak connector.

3.Install adapter (459) on the Switchpak (300) shaft with setscrew (465). Set the Switchpak SW20N-M in place onto the coupling (455) and install the four bolts (458), flatwashers (461), and lockwashers (462).

4.Install electrical conduit for the MEC as follows:

a)Standard connections for Switchpak SW20N-AM and motor:

Off the Switchpak, assemble 1 NPT x 3/4 NPT reducer (322), 3/4 NPT close nipple (310), seal enclosure (315), seal cover (314), 3/4 NPT x 2.75 long nipple (313), field power supply connection enclosure (334), 3/4 NPT x 2.75 long nipple (313), 3/4 NPT capped elbow (321), 3/4 NPT x 3.50 long nipple (312), and the 3/4 NPT union (320) to the motor terminal box. Install 3/4 NPT plugs for the enclosures and 1/2 NPT plug for the seal cover.

b)Optional connections for local control station:

Off the Switchpak pedestal, assemble the local control station (350), STEP/JOG pushbutton (356), REMOTE/JOG/STEP 3-position switch (357), 3/4 NPT x 3 long nipple (318), 3/4 NPT capped elbow (321), 3/4 NPT x 2.50 long nipple (317). Thread into the seal enclosure (315) until the back of the control station is flush with the Switchpak pedestal. Loosely install bolt (351), flatwashers (353), lockwashers (354), and nut (352). Use spacer (358) if required. Install 3/4 NPT plug for the control station.

c)Optional connections for digital display:

Off the Switchpak pedestal, loosely install the display bracket (506) with bolts (516), lockwashers (520), flatwashers (522), and nuts (518). Connect digital display enclosure (500) to seal enclosure (315) with 3/4 NPT x 2 long nipple. Loosely attach display enclosure to bracket with bolts (508), lockwashers (512), flatwashers (514) and nuts (510). Install positional display board assembly (502) to enclosure (500) with standoff (504) and screws (505).

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