Block 2 - 5A - Synchro and Servos

What is the general purpose of synchro/servo systems?

• To transfer mechanical or angular position information electrically to an indicating device.

• To transfer electrical position information mechanically or angularly to an indicating device.

• To transfer heat position information to an electrical indicating device

• To transfer positioning information through audio waves

How many types of synchro/servo systems are there?

• 3

• 4

• 2

• 5

Answer explanation

The three types are

1. Torque/Pure Synchro Systems (AC)

2. Position (selsyn) transmitter synchro (DC)

3. Servo system

Which system transfers angular position information electrically to an indicating device?

• Torque/Pure synchro system

• Pure/Intertia system

• Torque/Pure transmitter

• Pure receiver

Answer explanation

Described in first paragraph of page 5-3 (79/89)

What are two components of synchros?

• Synchro transmitter, synchro receiver

• Electrical zero, correspondence

• Selsyn, bus adapter unit

• Servo, control transformer

Synchro transmitter is also known as

• Torque transmitter (tx)

• Torque receiver (trx)

• Control transmitter (cx)

• Torque/pure (AC)

The abrupt or sudden movement of an indicator needle

Electrical zero is described as

• Synchros aligned to a common reference

• Synchros in correspondence

• The friction required to control the indicator needle

• When current reaches zero when armature reaches perpendicular position

Synchros are designed to operate on 24V AC or 115 V DC

• True

• False

Answer explanation

Designed to operate at 26V AC or 115 V AC

How far is the spacing of stator coils?

• 130 degrees

• 120 degrees

• 180 degrees

• 100 degrees

Answer explanation

Remember that spacing 120 degrees apart allows the strongest part of magnet field of the rotor coil are only near one of the coils at a time.

A synchro transmitter is to a generator as a synchro transmitter is to a