User Guide

Warning:

• Disconnect the power supply (line power) before installation to prevent electrical shock

and equipment damage.

• Make all connections in accordance with the wiring diagram and in accordance with

national and local electrical codes. Use copper conductors only.

Caution:

• Do not apply power to the unit unless the damper linkage and/or the valve assembly

have been installed.

• Avoid locations where excessive oil, dust, moisture, corrosive fumes or vibration, or an

explosive atmosphere is present. The actuator case is intended primarily to provide a

degree of protection against windblown dust, rain, sleet, and external ice formation

(NEMA Type 4).

Mounting Mount the actuator according to the following requirements:

1. Allow a minimum of 6” (152 mm) clearance behind the actuator for access to the wiring

compartment.

2. Locate the actuator in a weather-protected area.

3. To ensure water and weather resistance, install the cover gasket (provided) and use

water-tight conduit fittings.

Dampers

Install the actuator and the damper linkage, so that 180° of actuator shaft rotation drives 90°

of damper shaft rotation, as follows:

Actuator Mounting and Damper Linkage Installation

1. Mount the actuator in an appropriate position near the damper.

Note:

• MA-305 and MA-405 series actuators are not position-sensitive, and in damper

applications, may be mounted in any position. However, the upright position is

preferred.

• MA-318, MA-416, MA-418, and MA-419 series actuators must be mounted so that the

output shaft lies in a horizontal position.

• To the extent possible, position the actuator to optimize the length of the damper rod

needed to link it with the damper. A damper rod that is too long is not rigid enough for

good control, and a damper rod that is too short makes it difficult to adjust the linkage.

2. Install crank arms onto the driven shaft and the actuator shaft. Tighten the crank arm

on the driven shaft. Do not tighten the crank arm on the actuator shaft at this time.

3. Install a linkage connector onto the actuator shaft crank arm, at the prick point. Refer to

Figure-3 and Figure-4.

Prick Point

123

Slot provides adjustment

from 7/8" to 3-1/8".

Figure-3 Location of Prick Point on Crank Arm.