Bently Nevada 136491-01 3500/62 -10/+10 Vdc I/O Module

Bently Nevada 136491-01 -10 to +10 Vdc I/O module for the 3500/62 process variable monitor

The Bently Nevada 136491-01 is the rear I/O module of the 3500/62 Process Variable Monitor that accepts voltage inputs from -10 Vdc to +10 Vdc, with internal terminations. The manufacturer lists it as the spare “-10 Vdc to +10 Vdc I/O Module with internal terminations”. Field wiring from the process transmitters lands directly on the terminals of this module, and the module connects through the rack backplane to the six-channel 3500/62 main module.

In the ordering code 3500/62-AA-BB, 136491-01 is the A01 option. The other I/O modules in the family are 136499-01 (the same voltage input with external terminations), 136294-01 and 136483-01 (isolated 4-20 mA, internal and external) and 137110-01 (4-20 mA with internal barriers). Seven Star LLC supplies 136491-01 in Oman and the GCC as an independent supplier in Muscat.

What the 3500/62 does with a voltage input

The 3500/62 is a six-channel monitor for machine parameters that deserve continuous attention but are not vibration, for example lube oil pressure, process flow, bearing-area temperature signals converted to voltage, or level. It conditions the incoming signal, scales it to engineering units set in the 3500 Rack Configuration Software, and compares the result with user alert and danger setpoints. The result can drive the rack relays and the rack communication gateways like any other monitor channel.

With the 136491-01 module a channel can be configured for any proportional voltage between -10 Vdc and +10 Vdc. The datasheet states that the minimum input signal span for voltage input is 2 volts, and the full-scale range of each channel is set in the field, with no calibration needed.

136491-01 technical specifications

Why choose the internal-termination voltage module

Internal terminations keep the installation simple: wires connect to the module and no extra cable or termination block is needed. This suits small racks and retrofits where the existing field wiring already lands on rear modules. External termination blocks cannot be used with internal-termination modules, so the choice must follow the wiring philosophy of the cabinet. If the plant wants all field wiring on cabinet-wall blocks, the 136499-01 external version is the matching module, together with block 136595-01 (terminal strip) or 136603-01 (Euro style) and cable 134544-AAAA-BB.

Where 136491-01 fits in the 3500 system

• Main module partner: the 3500/62 monitor, spare number 163179-03, which holds the signal processing and the firmware IC 136590-01.
• Rack: any full-height monitor slot; the I/O module goes in the corresponding rear slot.
• Software and firmware: adding the 3500/62 to an existing system requires 3500/20 firmware 1.07 (Rev G), 3500/01 software 2.20, 3500/02 2.10 and 3500/03 1.20 or later.
• Fuse: the 250 mA, 250 V fast-blow fuse applies to the barrier I/O types only, not to 136491-01.
• Triple modular redundant units of the 3500/62 are stated to be no longer available for purchase.

Selecting between the 3500/62 I/O modules

Use the voltage module when the transmitter delivers a voltage output directly, or when a converter or DC-output sensor already supplies -10 to +10 Vdc. For loop-powered 4-20 mA transmitters pick one of the current modules instead. Note the 4-20 mA barrier I/O has a compliance of 13.66 V and an input impedance of 50 Ω, which is a different electrical interface from the 1 MΩ voltage input of 136491-01.

Installation, commissioning and maintenance of 136491-01

Wire the shields and signal pairs according to the 3500/62 field wiring diagrams, keeping voltage signal pairs away from power cabling because a 1 MΩ input is more sensitive to induced noise than a 50 Ω current loop. Use an anti-static strap when handling the module.

For commissioning, configure the channel in the Rack Configuration Software as voltage input, enter the full-scale range and engineering unit, then inject a known voltage from a calibrator at several points and compare the displayed value. Check Alert and Danger setpoints and time delays, and confirm that the bypass LED and the OK LED behave as expected. A spare 136491-01 in the store lets a failed channel set be restored quickly, as the I/O module is the part exposed to field faults.

Typical applications in Oman and the GCC

Process variable monitors in Oman and the GCC watch auxiliary signals around gas turbines, compressors and pump trains: lube oil header pressure, seal gas differential pressure, cooling water flow, and tank or sump level. Voltage-input channels are common where a DCS or a signal conditioner already outputs a scaled voltage, and in older installations that were wired before 4-20 mA became standard. Heat and dust in field junction boxes make clean shielding and tight terminal checks part of every inspection.

Information to send with your RFQ for 136491-01

• Part number 136491-01 and quantity.
• Label photo of the I/O module and of the 3500/62 main module (revision and serial number).
• Type of field signal and its range, so the input type can be confirmed.
• Delivery location in Oman or the GCC and required date.

Related Bently Nevada products: Bently Nevada 128240-01 3500/42M Prox/Seismic I/O Module, Bently Nevada 125680-01 3500/40M Proximitor I/O Module, Bently Nevada 149369-01 3500/25 Enhanced Keyphasor Module, Bently Nevada 3500/20 Rack Interface Module, Bently Nevada 3500/60-01-00 Temperature Monitor Module and Bently Nevada 3500/50 Tachometer Module.

Documents and quotation

The 3500/62 datasheet is attached on this page and the figures above follow its content.

Send the part number 136491-01 with your rack details and Seven Star LLC will confirm availability and lead time in the quotation for Oman and the GCC.