Protection Relays Voltage Monitoring Relays 355 SERIES 3-phase voltage/phase monitor Description The 355 series is a 3-phase voltage monitor with adjustable trip and restart delay, adjustable voltage unbalance and multiple diagnostic lights. It is perfect for heavy-duty applications that need both protection and simple user-friendly diagnostics. Applications include pump panels, commercial HVAC, oil rigs and others. The 355 series uses microcontroller technology to monitor incoming voltage and de-energize its output relay if power problems exist. The 355 series can protect motors from damage caused by single-phasing, high and low voltage, phase reversal and voltage unbalance. It has four diagnostic LEDs that clearly show overvoltage, undervoltage, voltage unbalance, reverse- phase and normal conditions. The 355200 is equipped with a heavy-duty 10 A general purpose SPDT relay. The 355400 and 355600 are equipped with a 470 VA 600 V ac pilot duty SPDT relay. A high voltage (600 V) DPDT Wiring Diagram relay output option is available with the 400 V model. TYPICAL WIRING DIAGRAM FOR MODEL 355 WITH MOTOR CONTROL Features & Benefits FEATURES BENEFITS Proprietary Constantly monitors 3 phase voltage to protect microcontroller against harmful line conditions, even before the based circuitry motor is started Provides diagnostics which can be used for Advanced LED indication troubleshooting and to determine relay status Prevent nuisance tripping due to rapidly fluctuating Adjustable trip and power line conditions and allows staggered start up restart delay settings of multiple motors, after a fault, to prevent a low voltage condition Combines protection Perfect for heavy duty applications: pump panels, and diagnostics commercial HVAC, and oil rigs 600 V rated relay Eliminates the need for a control transformer to step contacts available voltage down to 120240 V for a control circuit on some models TYPICAL WIRING DIAGRAM FOR MODEL 355 WITH ALARM CONTROL Ordering Information MODEL LINE VOTAGE DESCRIPTION 355200 190240 V ac SPDT 355400 380480 V ac SPDT 3554005 380480 V ac DPDT 355600 475600 V ac SPDT 2020 Littelfuse, Inc. Rev: 1-A-062716Rev: 2-A-061220 wwwwww.littelfuse.com/355.littelfuse.com/Protection Relays Voltage Monitoring Relays 355 SERIES General Characteristics Specifications Temperature Range Input Characteristics Operating -40 to 70C (-40 to 158F) Line Voltage Storage -40 to 80C (-40 to 176F) 355200 190240 V ac Repeat Accuracy 355400 380480 V ac Fixed Conditions 0.1 % 355600 475600 V ac Maximum Input Power 6 W (Specify voltage range) Terminal Frequency 50*/60 Hz Torque 7 in.-lbs. Functional Characteristics Wire Size 12-18 AWG Low Voltage (% of setpoint) Transient Protection Trip 90 % 1 % (Internal) 2500 V for 10 ms Reset 93 % 1 % Safety Marks High Voltage (% of setpoint) UL UL 508 (File E68520) Trip 110 % 1 % Dimensions H 74.42 mm (2.93) W 133.86 mm (5.27) Reset 107 % 1 % D 74.93 mm (2.95) Voltage Unbalance (NEMA) Weight 0.94 lb. (15.04 oz., 426.38 g) Trip 28 % adjustable Mounting Method 8 screws Reset Trip setting minus 1 % Special Options Trip Delay Time: Option 5 - DPDT Relay Low & High Voltage and Unbalance 230 seconds adjustable *Note: 50 Hz will increase all delay times by 20 %. Single-phasing Faults (>25% UB) 2 seconds Restart Delay Time After a Fault or Power Loss Manual, 2300 seconds adj. Output Characteristics Output Contact Rating SPDT (355200) Pilot Duty 480 VA at 240 V ac General Purpose 10 A SPDT (355400, 355600) Pilot Duty 470 VA 600 V ac DPDT (-5 Option) Pilot Duty 470 VA 600 V ac 2020 Littelfuse, Inc. Rev: 1-A-062716Rev: 2-A-061220 wwwwww.littelfuse.com/.littelfuse.com/355