© 2016 Littelfuse Protection Relays & Controls
Protection Relays
Voltage Monitoring Relays
www.littelfuse.com/350
Rev: 1-A-062716
Description
The 350 Series is a heavy-duty voltage monitor. This product
should be used when high current relays or dual contacts are
required, or 480V controls are used. Since the 350 Series uses
heavy-duty relays, it comes in fixed voltage range models rather
than a dual auto-ranging version like the Model 250.
The 350200 has a 15A general purpose contact. The 350400
provides a SPDT (Form C) relay rated to switch up to 600V,
allowing the use of 480V controls, eliminating the need for a
control power transformer to step the voltage down to
120-240V. Several DPDT (two Form C contacts) relay models
are also available.
The 350 microcontroller-based family of products are low cost
yet highly advanced solutions to heavy-duty problems. The 350
includes advanced single LED diagnostics. Five different light
patterns distinguish faults and normal operating conditions.
Other options such as high voltage trip and adjustable restart
delay are available.
Features & Benefits
FEATURES BENEFITS
Proprietary
microcontroller
based circuitry
Constantly monitors 3 phase voltage to protect
against harmful line conditions, even before the
motor is started
Advanced LED indication
Provides diagnostics which can be used for
troubleshooting and to determine relay status
Adjustable restart delay
(-2 models) settings
Allows staggered start up of multiple motors, after
a fault, to prevent a low voltage condition
600V rated relay
contacts available
on some models
Eliminates the need for a control transformer to step
voltage down to 120 - 240V for a control circuit
3-phase voltage/phase monitor
350 SERIES
Wiring Diagram
Ordering Information
MODEL LINE VOTAGE DESCRIPTION MODEL LINE VOTAGE DESCRIPTION
350200 190-240VAC SPDT, fixed trip and restart delay 35040026 380-480VAC
DPDT, 2 relays (1)10a. (1) 15A; fixed trip and
variable restart delay (manual, 2-300s)
3502002 190-240VAC
SPDT, fixed trip and variable restart delay
(manual, 2-300s)
35040028** 380-480VAC
DPDT, 2 relays 15A; variable restart delay
(no manual reset)
35020026 190-240VAC
DPDT, 2 relays (1)10a. (1) 15A; fixed trip and
variable restart delay (manual, 2-300s)
35040029 380-480VAC
SPDT, fixed trip and variable restart delay
(manual, 2-300s), plus high voltage detection
35020028** 190-240VAC
DPDT, 2 relays 15A; variable restart delay
(no manual reset)
350600 475-600VAC SPDT, fixed trip and restart delay
35020029 190-240VAC
SPDT, fixed trip and variable restart delay
(manual, 2-300s), plus high voltage detection
3506002 475-600VAC
SPDT, fixed trip and restart delay
(manual, 2-300s)
350400 380-480VAC SPDT, fixed trip and restart delay 35060026 475-600VAC
DPDT, 2 relays (1)10a. (1) 15A; fixed trip and
variable restart delay (manual, 2-300s)
3504002 380-480VAC
SPDT, fixed trip and variable restart delay
(manual, 2-300s)
35060028** 475-600VAC
DPDT, 2 relays 15A; variable restart delay
(no manual reset)
35040025 380-480VAC
DPDT, fixed trip and variable restart delay
(manual, 2-300s)
35060029 475-600VAC
SPDT, fixed trip and variable restart delay
(manual, 2-300s), plus high voltage detection
** These units are not equipped with Manual Reset.
