Product Details
The Yokogawa IP91*A, also cataloged as the IP91 Communication Module, operates as a dedicated hardware component for multi-protocol serial communication and data packet translation within Yokogawa DCS and SCADA networks.
Suffix Breakdown & Model Matrix
| Code Element | Specification / Description |
|---|---|
| IP91 | Base model designation for industrial serial communication module |
| *A | Style code Revision A specifying terminal pin layout and physical enclosure revision |
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | IP91*A |
| Brand | Yokogawa |
| Origin | Japan |
| Weight | 0.15 kg |
| Dimensions | Compact panel/slot mount module format |
| Operating Temp | -10 deg C to 60 deg C |
| Power Consumption | 12-24 VDC continuous operating supply |
| Module Type | Communication Module |
| Supported Protocols | Modbus RTU, ASCII, Binary |
| Serial Interface | RS-232C / RS-485 configurable communication lines |
| System Integration | Yokogawa DCS, SCADA, and field instrument networks |
Channel-to-Channel Isolation and Multi-Protocol Serial Conversion
The IP91*A module converts raw serial field communications, including Modbus RTU, ASCII, and Binary protocols, into digitized backplane data streams for control system processing. Built-in channel-to-channel galvanic isolation shields internal processing circuits from ground loops and common-mode noise across RS-232C/RS-485 field loops. This isolation maintains signal integrity during high-baud-rate data transmission between field instruments and central DCS controllers.
Frequently Asked Questions
Q: How are communication protocol selections configured on the IP91*A module?
A: Protocol selection between Modbus RTU, ASCII, and Binary modes is established via internal DIP switch configuration settings and system engineering software initialization.
Q: Does the IP91*A module tolerate live insertion or removal during active host operation?
A: Module replacement should only be performed when the module power terminal is de-energized or when the connected communication bus is set to an inactive state to prevent frame corruption on the host network.
Q: What ground potential differences can the internal isolation barrier withstand?
A: The internal galvanic isolation barrier provides dielectric protection up to 1500 VAC between field serial lines and the internal logic power ground.
Field Installation Guidelines
- Mounting: Secure the module on a standard 35 mm DIN rail or designated chassis mounting slot. Verify that side retaining latches lock fully to prevent physical dislocation under mechanical vibration.
- Power Wiring: Connect a regulated 12-24 VDC auxiliary power supply to the designated power terminals. Verify correct voltage polarity before energizing the unit.
- Signal Cabling and Shielding: Route serial communication lines using shielded twisted-pair cables. Terminate cable shields to the cabinet functional earth (FE) bus at a single point to prevent ground loop currents.
- Line Termination: Ensure proper 120 ohm bus termination resistors are enabled at both physical ends of RS-485 communication loops to eliminate signal reflections over long cable runs.
Additional Information
- 100% Genuine Parts: All products are original and authentic, ensuring reliable industrial performance.
- 30-Day Refund Guarantee: Return any in-stock item within 30 days in original, unopened packaging for a full refund (excluding shipping and fees).
- 12-Month Warranty: Covers defects in materials or workmanship; excludes misuse, normal wear, or unauthorized modifications.
- Worldwide Shipping: We ship via USPS, UPS, FedEx, and DHL. Delivery times vary by country and may be subject to customs or import fees.
- Support & Contact: Technical and warranty assistance is available anytime. Contact us here: Contact.
- Purchase Guidance: Check product specifications and compatibility carefully before ordering to ensure proper application.





























