Switching Inductive Loads - FlowLine DataView LI55 Series Quick Start Manual

DataView™ LI55 Level Controller

Switching Inductive Loads

Suppressors (snubbers) prevent microprocessor disruption and prolong the life of
the relay contacts and should always be employed. Suppression can be obtained
with resistor-capacitor (RC) networks assembled by the user or purchased as
complete assemblies. This section is provided to assist you with supressor
assembly and installation.
Choose R and C as follows:
R: 0.5 to 1 Ω for each volt across the contacts
C: 0.5 to 1 µF for each amp through closed contacts
When using suppressors, please keep in mind:
1. Use capacitors rated for 250 VAC.
2. Confirm proper operation. RC networks may affect load release time of
solenoid loads.
3. Install the RC network on the DataView's relay screw terminals. An RC
network may also be installed across the load.
4. Use a diode with a reverse breakdown voltage two to three times the circuit
voltage and forward current at least as large as the load current.
Note:
Relays are de-rated to 1/14th HP (50 watts) with an inductive load.
C
R
AC and DC Loads Protection
Low Voltage DC Loads Protection
Quick Start
C
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