M E A S U R E M E N T S Y S T E M S I N T E R N A T I O N A L
Page 70
MSI-3750 Digital Weight Indicator
◆
User Guide
terminal strips. After all the pins are connected, lightly wiggle and tug on
each wire to ensure that they are securely attached.
6)
Tighten the watertight feedthrough around the outer insulation to ensure the
water seal.
7)
Replace the front panel being careful to seat the gasket evenly around the lip
of the cabinet. Screw down the 10 screws in a criss-cross pattern to seat the
gasket evenly.
RELAY APPLICATIONS
Some examples of uses for the set point relays are: Using the normally open
position of a set point as a switch to turn on a light or siren when the set point is
reached, using the normally closed position to cut out a motor when a set point is
reached, or using the set point relays to change speeds on a motor. See Figure 1
for an example hook up to a lamp. The normally open (NO) contact of a relay is
used to turn devices on when a set point is reached, while the normally closed
(NC) contact is used to turn a device off when the set point is reached. The
common (COM) contact connects the power to the relay.
Neutral
Hot
Turn on a Lamp when the Setpoint is reached
NO
CM
NC
1A
SMD FUSE
Relay
Figure 1
Set points are often used in conjunction with automatic conveyer belts. By using
the set point relays, conveyor belts can be controlled by weight. Using two set
points allows speed control for dribbling or speeding up, etc. Figure 2 shows a
simple arrangement where the motor is turned off when a set point is reached.
Pay attention to the current and voltage ratings of the relay when using them for
motor control. It may be necessary to use a boost relay externally as in Figure 3.
NO
CM
NC
1A
SMD FUSE
Relay
Cut off a motor when the Setpoint is reached
Neutral
Hot
AC
MOTOR
Figure 2
Содержание MSI-3750
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