Dimensions:
241 mm x 24.4 mm x 99.1 mm (H x W x D)
Shipping port:
Xiamen
Warranty:
12 months
Description
The Bently Nevada 125720-01 is a spare 4-channel relay I/O module designed for use within the 3500/32 4-Channel Relay Module system. Installed in a full-height rear slot of a 3500 rack, it provides the physical terminal interfaces to route switching outputs to external control or machinery protection equipment.
The 125720-01 I/O module operates in conjunction with the front 3500/32 relay main module. Each of its four channels uses two single-pole, double-throw (SPDT) relays wired in a double-pole, double-throw (DPDT) configuration. Individual channels can be configured independently for Normally De-energized or Normally Energized operations and include onboard switches to select relay modes alongside standard 250 Vrms arc suppressors and epoxy environmental sealing.
Features
Epoxy-Sealed Relay Circuits: Constructed with epoxy sealing to protect switching components from environmental exposure.
Integrated Arc Suppression: Standard built-in 250 Vrms arc suppressors across relay contacts.
Switch-Selectable Operations: Individual channel switches allow configuration for Normally De-energized or Normally Energized modes.
DPDT Relay Configuration: Employs two SPDT relays per channel combined in a double-pole, double-throw setup.
Applications
3500 Series Machinery Protection Systems requiring discrete relay output interfaces
Automated machinery trip, alert logic actuation, and external control system interfacing
Industrial rotating equipment monitoring systems
Technical Specifications
Parameter
Specification
Manufacturer
Bently Nevada
Country of Origin
U.S.A
Module Type
Spare 4-Channel Relay I/O Module
Relay Type
Two SPDT relays connected in a DPDT configuration per channel
Environmental Sealing
Epoxy-sealed
Arc Suppressor
250 Vrms, installed as standard
Contact Life
100,000 cycles @ 5 A, 24 Vdc or 120 Vac
Operation Modes
Switch selectable per channel for Normally De-energized or Normally Energized
Max Switched Power (Resistive)
DC: 120 W; AC: 600 VA
Min Switched Current
10 mA @ 5 Vdc
Max Switched Current
5 A
Max Switched Voltage
DC: 30 Vdc; AC: 250 Vac
Operating Temperature
-30 degC to +65 degC (-22 degF to +150 degF)
Storage Temperature
-40 degC to +85 degC (-40 degF to +185 degF)
Humidity
95%, non-condensing
Dimensions (H x W x D)
241 mm x 24.4 mm x 99.1 mm (9.50 in x 0.96 in x 3.90 in)
Weight
0.4 kg (1.0 lb.)
Rack Space Requirements
1 full-height rear slot
Installation Guidelines
Slot Placement: Mount the 125720-01 into a full-height rear slot directly behind its corresponding 3500/32 front relay module.
Terminal Connections: Connect wiring from external alarm and shutdown devices to the designated terminal connectors on the rear faceplate.
Mode Selection: Set the relay mode switches on the module faceplate to Normally De-energized (NDE) or Normally Energized (NE) as required by the system control scheme.
ESD Protection: Use a single-use grounding wrist strap (p/n 04425545) or equivalent protection when handling or installing the card.
Compliance and Certifications
Certification / Standard
Detail
Safety Requirements
EN 61010-1
EMC Directives
IEC 61000-6-4 (Radiated/Conducted EN 55011 Class A), IEC 61000-6-2 (EN 61000-4-2, ENV 50140, ENV 50141, EN 61000-4-4, EN 61000-4-5, EN 61000-4-8, EN 61000-4-11, ENV 50204)
Hazardous Area Approvals
CSA/NRTL/C (Class I, Div 2, Groups A, B, C, D; T4 @ Ta = -20 degC to +65 degC)
FAQ
What is the Bently Nevada 125720-01 used for?
The Bently Nevada 125720-01 is a spare 4-channel relay I/O module used to connect external alarm and control devices to the 3500/32 relay system.
Which system does the 125720-01 module belong to?
The module belongs to the Bently Nevada 3500 Series Machinery Protection System and serves as the rear I/O component for the 3500/32 4-Channel Relay Module.
What are the contact electrical ratings for the relay outputs?
The relay outputs handle maximum switched currents up to 5 A, with voltage limits of 30 Vdc or 250 Vac, and maximum resistive loads of 120 W DC or 600 VA AC.
How are the operation modes configured on the module?
Each channel is individually selectable for Normally De-energized or Normally Energized operation via switches located on the module.
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