Siemens ET 77E Series Especificaciones descargar pdf (Pagina 33)

SD77

5.4 COIL ASSEMBLY REPLACEMENT

Removal

When the transducer's top housing is removed, care must be taken to prevent metal chips, dirt, and other

contaminants from entering the coil chamber. These foreign objects can interfere with coil movement and may

change the magnetic field.

Refer to the parts list at the rear of this Instruction and the following procedure.

1. Remove the top housing.

2. Remove the brass clamping plate. It is held by a single screw.

3. Remove the two Teflon washers.

4. Slide the bowed “E” retaining ring off the shaft.

IMPORTANT

Do not bend the center shaft. Support the shaft while removing the retaining ring.

5. Remove the coil assembly by carefully lifting it off the center shaft.

Installation

Refer to the parts list at the rear of this Instruction and the procedure that follows.

IMPORTANT

The coil assembly and coil chamber must be free of metal chips, dirt and corrosion

before installing the coil.

1. Lower the coil assembly onto the center shaft and, at the same time, guide the leaf springs onto the contact

posts

2. Install the bowed “E” retaining ring on the center shaft - bowed center up.

3. Install the Teflon washers (small diameter up), clamping plate, and clamping plate screw. Do not tighten the

screw at this time; it must be loose until the coil is aligned. Refer to the Alignment procedure below.

Alignment

Center the coil so that it does not rub against the transducer housing or the pole piece under the coil. It must also be

positioned so that the leaf springs do not buckle or snap.

Make three cardboard or paper shims 0.012" thick x 1-1/2" long x 3/8"

wide. These can be made from a matchbook cover.

Refer to Figure 5-1 and use the following procedure.

1. If not already accomplished, loosen the spring clamping plate

screw.

2. Insert the shims between the coil and the housing at the points

shown in Figure 5-1. Insert the shims until their ends are flush with

the top surface of the housing. Then, raise the coil to a higher point

on the shims by pulling the center shaft up.

FIGURE 5-1 Coil Alignment

1 2 ... 28 29 30 31 32 33 34 35 36 37 38 ... 41 42

Sin comentarios

Siemens ET 77E Series Especificaciones Pagina 33