NKK Switches • email: sales@nkkswitches.com • Phone (480) 991-0942 • Fax (480) 998-1435 • www.nkkswitches.com

05-08

Half-Inch Diameter Process Sealed Rotaries

Series MR

Pole

Model

Number of Positions

Stopper Settings

Number of Terminals

Schematics

SP

MRA112

MRF112

MRK112

2–12

2–12

2–12

2, 3, 4, . . . 12

2, 3, 4, . . . 12

2, 3, 4, . . . 12

1 COM, 12 LOAD

1 COM, 12 LOAD

1 COM, 12 LOAD

DP

MRA206

MRF206

MRK206

2–6

2–6

2–6

2, 3, 4, 5, 6

2, 3, 4, 5, 6

2, 3, 4, 5, 6

2 COM, 12 LOAD

2 COM, 12 LOAD

2 COM, 12 LOAD

4P

MRA403

MRF403

MRK403

2–3

2–3

2–3

2, 3

2, 3

2, 3

4 COM, 12 LOAD

4 COM, 12 LOAD

4 COM, 12 LOAD

POLES & CIRCUITS

12 34 56 78 9101112

A

12 34 56 12 34 56

A

B

12 31 23 12 31 23

A

B

C

D

POSITION SETTING FOR MRA, MRF, & MRK MODELS

Each switch is supplied with the stopper set for the maximum number of positions allowed for that model. Prior to installation,

the desired position setting should be made. Contact factory for continuous rotation.

MRF Models

1. Remove the protective cover from the switch body.

2. Turn the shaft counterclockwise to the extreme left by using a screwdriver.

3. Inside the cover is a magnifying lens which would be positioned over the

number which is to be the maximum position used; when the cover is then

snapped into the switch, the projection beside the lens fits into the correct

hole for setting the stop.

2

-

4 5 6

Protective Cover

Lens

Projection

MRK & MRA Models

1. Using the actuator knob, turn the shaft

counterclockwise to the extreme left. If

the shaft is not turned counterclockwise

to the extreme left, proper setting can-

not be achieved. At this extreme posi-

tion, the white line on the knob points

to the number 1 position shown on the

side of the switch.

2. Remove the knob from the shaft and

loosen the nut far enough to allow rais-

ing the stopper plate, plus washer(s),

for resetting to the desired position.

3. Note the position numbers on the side

of the switch; these correspond to the

terminal numbers and stopper holes.

Insert the stopper in the hole numbered

for the maximum desired number of

stop settings. Satisfactory switch func-

tioning cannot be assured if the stopper

plate is not properly positioned.

4. Tighten the nut (beveled side up) firmly

against the stopper plate.

12

11

10

9

1

12

11

10

2

2

1 C

12

11

10

9

12 11 10

9

Standard Mounting Hardware

Packaged Loose with Each Switch:

Hex Face Nut

Locking Ring

Lockwasher

Rubber Ring (MRK)

Factory Assembled:

Hex Nut

Stopper Plate

Metal Washer (MRA)

Rubber Washer