Metrix 5550 User Manual

Doc# 1231558 • REV C (November 2017) Page 17 of 20
• Cool-Down Period
If the circuit acvang the startup delay leaves the voltage connuously applied (as
is typical), the thermistor will remain hot unl voltage is removed, such as follow-
ing a machine trip. Thus, when the thermistor is not allowed to cool to its ambient
surroundings, it will shorten the startup delay.
• Immediate Restart
If a restart is required immediately following a trip, the thermistor may be so hot
that the switch cannot be immediately reset using the remote reset funcon. In
such situaons, it will be necessary to either manually reset the switch or wait for
the thermistor to cool suciently. Alternavely, it may be desirable to modify the
machinery control logic such that voltage is only applied to the reset terminals for
the duraon of the factory pre-set delay, ensuring that the thermistor circuit is only
energized at startup.
• Current Flow
The amount of current owing through the thermistor will be a funcon of the volt-
age applied, the thermistor’s resistance, and the resistance elsewhere in the circuit.
Loose, intermient, or corroded wiring connecons can increase resistance and result
in a longer startup delay interval. If the resistance is too great, the reset coil will not
energize at all due to insucient current. Insucient voltage and/or current can also
be a problem. Be certain that the coil voltage rang (ordering opon D) matches the
voltage and current your circuit supplies. See Table 1 on the following page.
Opon D
(coil voltage)
Opon C
(coil holding
force)
Rated
Voltage
Min
Voltage
Max
Voltage
Min
Current
Max Power
Consumpon
None (D=0) All N/A N/A N/A N/A N/A
115 Vac (D=1) All 115 Vac 103.5 Vac 126.5 Vac 1.24 A 287.5 W
230 Vac (D=2) All 230 Vac 207 Vac 253 Vac 0.32 A 230 W
24 Vdc (D=3) 5 g (C=1) 24 Vdc 22.8 Vdc 25.3 Vdc 1.58 A 60 W
2 g (C=2) 24 Vdc 22.8 Vdc 25.3 Vdc 1.18 A 28.8 W
10 g (C=3) 24 Vdc 22.8 Vdc 25.3 Vdc 2.88 A 72 W
115 Vdc (D=4) All 115 Vdc 103.5 Vdc 126.5 Vdc 1.20 A 207 W
Table 1: Reset / Startup Delay Coil Electrical Characteriscs
5.3 Coil Consideraons
5.3.1 Coil Hold Strength
The reset / startup delay coil is sized to provide a specied holding strength (opon C), al-
lowing the startup delay feature to hold the switch in its untripped state even in the pres-
ence of high vibraon encountered during machine startup. If the reset coil supplied will
not hold the switch in an untripped state during startup, it may be the wrong size. Refer
to Table 1 and consult the factory for assistance.

Metrix 5550 Specifications

General

Brand	Metrix
Model	5550
Category	Switch
Language	English