6ES7972-0BB12-0XA0 Siemens Bus Connector

フルモデル & Official Description

注文番号: 6ES7 972-0BB12-0XA0

SIMATIC DP, PROFIBUS Bus Connector, まで 12 メガビット/秒; 90° vertical cable outlet, with PG programming socket, integrated switchable isolated termination resistor, ネジ端子配線.

モデルコードの内訳

コードセグメント	意味
6ES7	SIMATIC S7 automation system accessories
972	PROFIBUS RS485 bus connector series
0BB	90° outlet + with PG programming socket; 0BA = without PG socket
12	ネジ端子 (non-FastConnect stripping structure)
0XA0	標準一般バージョン (Made in Germany)

コア電気 & 機械仕様
Communication Standard: プロフィバス-DP / MPI (RS485)
Max Baud Rate: 12 メガビット/秒
Termination Resistor: Built-in 220Ω, ON/OFF toggle switch (孤立しながら)

Termination switch set to ON for the first and last station on the bus; OFF for all intermediate stations

配線方法: ネジ端子, conventional cable stripping, FastConnect cable is NOT supported
Interfaces: Rear 9-pin Sub-D male connector; independent front 9-pin PG female socket (online debugging without bus interruption)
ケーブルコンセント: 90° vertical downward outlet, suitable for compact cabinet installation
全体の寸法: 15.8 mm(W) × 64 mm(H) × 35.6 mm(D)
保護クラス: IP20 (indoor cabinet installation only)
温度範囲: オペレーティング: 0 ℃～ +60 ℃; ストレージ: -40 ℃～ +70 ℃
正味重量: 約. 60 g
配線の定義 (Standard PROFIBUS Purple Cable)

Terminal A: Green signal wire

Terminal B: Red signal wire

> ⚠️ Reversing A/B will directly trigger communication failure; secure the cable shield to the connector metal clamp with grounding at both cable ends.

Cross Comparison of Similar Models (選定基準)

注文番号	Outlet Angle	PG Socket	配線タイプ
6ES7972-0BB12-0XA0	90°	✅ Yes	ネジ端子 (このモデル)
6ES7972-0BA12-0XA0	90°	❌ No	ネジ端子
6ES7972-0BB42-0XA0	35° angled outlet	✅ Yes	ネジ端子
6ES7972-0BB52-0XA0	35° angled outlet	✅ Yes	FastConnect quick stripping

適用デバイス & Scenarios

S7-300 / S7-400 CPU DP ports

ET200M, ET200S DP interface modules

PROFIBUS-DP inverters, サーボドライブ, 楽器, エンコーダ

S7-200 SMART RS485 (MPI/DP mode)

Key Application Notes & Common Pitfalls
FastConnect quick stripping technology is not supported. FC cables cannot be directly crimped; select 0BB52 / 0BA52 series if FC cables are used.
Online monitoring via PG socket does not require bus disconnection, ideal for non-stop equipment debugging.
Only enable termination resistors at the two ends of one PROFIBUS bus. Multiple active termination resistors cause unstable communication and packet loss.
Avoid excessive tension on terminals during cable bending. Reliably crimp the shield; dual-end grounding is strongly recommended for long-distance communication.
Wide-Temperature Special Version (For Harsh Environments)

6AG1972-0BB12-2XA0 (SIPLUS Version)

Derived from 6ES7972-0BB12-0XA0 with anti-corrosion coating. 動作温度: -25℃～+70℃, applicable to outdoor, 空調設備, metallurgy and high-humidity environments.

交換情報

Direct form-fit replacement: Prioritize identical part number for no hardware modification.

If 35° angled outlet is required: Replace with 6ES7972-0BB42-0XA0.

For new projects, prefer FastConnect version 6ES7972-0BB52-0XA0 for higher wiring efficiency.

Supplementary Document: PROFIBUS DP Topology, 配線仕様 & トラブルシューティングマトリックス

Compatible with 6ES7972-0BB12-0XA0 Bus Connector

Standard PROFIBUS Bus Topology (Linear Topology; Star/Tree Topology Forbidden)

Mandatory Topology Rules

Linear daisy-chain connection only; T-branches and star wiring are strictly prohibited. Branches cause signal reflection, communication jitter and packet loss.
Set termination resistor to ON only on the first and last connectors of the whole bus; all intermediate stations must be set to OFF.
Maximum two cables (で / 外) per bus connector. Do not terminate multiple wires on one screw terminal.
Detailed Wiring Specification for 6ES7972-0BB12-0XA0

2.1 端子の定義

あ: Green wire

B: Red wire

> ⚠️ Red = B, Green = A. A and B must not be swapped.

2.2 Shield Handling

Unfold the metal shielding braid of PROFIBUS purple cable; do not cut off the copper mesh.
Lay shielding braid flat and clamp under the metal shield clip of the connector.
Cabinet layout recommendation: Reliably ground the shield at both ends of the bus. Dual-end grounding is preferred for long-distance and high-interference sites; single-end grounding is adopted if potential difference exists between ground points.
Never short shielding braid with signal wires A/B!

2.3 Termination Resistor Switch Operation

の上: 220Ω termination resistor activated (for first & last station)

オフ: Termination resistor disconnected (all intermediate stations)

> Typical Fault: Multiple stations with termination resistor ON → Impedance mismatch, frequent communication errors.

2.4 PG Programming Socket Instructions

This model integrates a 9-pin female PG socket:

Programming cable can be plugged for online monitoring without cutting off the bus.

⚠️ PG socket is only for temporary debugging; do not permanently connect other slave devices.

Step-by-Step Wiring Procedure
Unscrew and open the connector housing;
Strip outer cable sheath, remove 6~7mm insulation of red/green cores;
Route red wire to terminal B, green wire to terminal A. Tighten screws with torque 0.4~0.6Nm (avoid thread slipping);
Clamp shielding braid into metal shield clip;
Verify no short circuit between A and B, no exposed conductors touching each other;
Toggle termination resistor switch according to station position;
Close housing, insert connector into module Sub-D port and lock fixing screws.
PROFIBUS DP Communication Troubleshooting Matrix

故障の症状	根本的な原因	Stepwise Remedial Actions
All stations offline; master reports DP fault (BF LED steady red)	1. Termination resistors disabled at both ends	1. Check two end connectors, set termination switch to ON
	2. A/B reversed for the whole bus	2. Verify A(緑)/B(赤) wiring section by section
	3. A/B short-circuit somewhere on bus	3. 電源を切る, use multimeter to check A-B short circuit
	4. Broken bus cable	4. Isolate cable segments to locate break point
Random drop-out of partial slaves, flashing BF LED, 断続的な通信	1. Termination resistor mistakenly enabled on intermediate stations	1. Inspect termination switch on every connector
	2. シールドの接地不良 & electromagnetic interference	2. Re-tighten shield crimp and grounding bar
	3. Cracked/bent cable insulation	3. Rewire to eliminate all branch lines
	4. Branched (星) bus wiring	4. Cross-check baud rate vs maximum cable length table
	5. Baud rate too high, bus length exceeds limit
Devices near master run normally, remote slaves drop out frequently	1. Bus length exceeds limit corresponding to selected baud rate	1. Reduce communication baud rate
	2. Ground loop interference caused by multi-point grounding	2. Optimize shield grounding scheme
	3. Low-quality non-standard PROFIBUS Type A cable	3. Replace with certified PROFIBUS Type A cable
Communication fails after PG cable insertion; restored after unplugging	PG cable contains built-in termination resistor, conflicting resistance at bus terminal	Avoid long-term PG connection on end-node connectors; use PG socket on intermediate stations for debugging
Communication works after commissioning, failure occurs after equipment vibration	Loose screw terminals, ワイヤーの接触不良; cable tension pulling connector	端子ネジの増し締め; fix cables with cable ties to avoid mechanical load on connectors

Baud Rate — Maximum Cable Length Table (PROFIBUS Type A Cable)

ボーレート	最大バス長
9.6 kbit/s	1200 メートル
19.2 kbit/s	1000 メートル
187.5 kbit/s	400 メートル
500 kbit/s	200 メートル
1.5 メガビット/秒	100 メートル
3 ～ 12 メガビット/秒	100 メートル

Strict Forbidden Operations (Red Line Rules)
❌ Do not terminate more than two signal wires under one screw terminal
❌ Do not construct PROFIBUS bus with star topology or T-branches
❌ Do not activate termination resistor on multiple stations simultaneously
❌ Do not swap signal wire A and B
❌ Do not short shielding braid with A/B conductors
❌ Do not replace standard PROFIBUS Type A cable with ordinary 2-core cable
❌ Do not sharply bend cable near the connector outlet to prevent internal wire fracture
Additional Selection Reminder

6ES7972-0BB12-0XA0 adopts screw terminal wiring and does NOT support FastConnect cables.

For new mass rollout projects, it is recommended to select:

6ES7972-0BB52-0XA0 (35° outlet + PG socket + FastConnect)