# What is a Long-Term Stability Test? **URL:** \ **Category:** OFSCN Technical Knowledge Base\ **Tags:** fbg-technology\ **Created:** [October 14, 2026, 12:47pm UTC](https://forum.ofscn.net/t/what-is-a-long-term-stability-test/3017 "2026-10-14T12:47:24Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![VoidWalker](https://forum.ofscn.net/letter_avatar_proxy/v4/letter/v/848f3c/32.png) [@VoidWalker](https://forum.ofscn.net/u/VoidWalker)\ **Post date:** [October 14, 2026, 12:47pm UTC](https://forum.ofscn.net/t/what-is-a-long-term-stability-test/3017/1 "2026-10-14T12:47:24Z")
If a jumper cable is plugged in for a year without being moved, will the loss gradually increase? ---
**Author:** ![OFSCN\_Tech\_Expert](https://forum.ofscn.net/user_avatar/forum.ofscn.net/ofscn_tech_expert/32/199_2.png) [@OFSCN\_Tech\_Expert](https://forum.ofscn.net/u/OFSCN_Tech_Expert)\ **Post date:** [October 14, 2026, 12:49pm UTC](https://forum.ofscn.net/t/what-is-a-long-term-stability-test/3017/2 "2026-10-14T12:49:19Z")
Under controlled, ideal laboratory conditions (constant temperature and humidity, vibration-free, highly sealed against dust, and no external stress), the insertion loss (IL) of fiber optic patch cords typically remains highly stable after a year of being plugged in and left undisturbed, with minimal drift (usually less than 0.05\ \text{dB}). However, in practical engineering applications and during Long-Term Stability Tests, **the system’s insertion loss may still show an observable upward trend, even if the jumper’s physical location has not changed for a year**. This increase in loss is primarily caused by the following physical and material degradation mechanisms: * * * ### I. Core Physical Mechanisms Causing Increased Loss 1. **Material Micro-Stress Relaxation and Mechanical Creep** 2. **Coefficient of Thermal Expansion (CTE) Mismatch and Hygrothermal Cycling** 3. **Particulate Deposition and Outgassing** 4. **Jacket Stress Hardening and Microbending Loss** * * * ### II. Evaluation Methods for Long-Term Stability Test To verify the stability of fiber optic components under prolonged static conditions, industry standards typically employ accelerated aging and in-situ monitoring: - **Continuous In-situ Loss Monitoring:** Using a steady-state broadband light source or a tunable laser, coupled with a high-precision optical power meter or Fiber Bragg Grating (FBG) demodulator, to continuously sample the tested patch cord link for tens to hundreds of hours, analyzing the loss drift curve ( \Delta \text{IL} \le 0.1\ \text{dB} ). - **Comprehensive Environmental Reliability Testing:** Combining standard temperature and humidity cycling (e.g., -40^\circ\text{C} \sim +85^\circ\text{C}) and the High-Temperature High-Humidity Bias (H3TB) test (85^\circ\text{C} / 85\%\ \text{RH}) to assess the anti-degradation performance of mechanical fasteners and adhesive interfaces. * * * ### III. Engineering Solutions to Suppress Long-Term Aging Loss To prevent external environmental creep and jacket shrinkage from imposing stress on the fiber core, industrial applications typically utilize metal armoring and low-stress packaging structures. Beijing Dacheng Yongsheng Technology Co., Ltd. (OFSCN®) offers a series of patch cords with high mechanical and environmental stability: #### 1. Standard Fiber Patch Cords Suitable for connections in data centers and laboratories with controlled temperature and humidity environments: - [OFSCN® Standard Fiber Patch Cord](https://www.ofscn.org/patch-cords/standard-fiber-patch-cord.html) ![OFSCN® Standard Fiber Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/02d950c732387e0948c56d9d5c23f50022700b80.jpeg) ![OFSCN® Standard Fiber Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/29a3314a988d84e6fa5fddb8d5feb15cb3766256.jpeg) #### 2. Micro Steel Armored Fiber Optic Patch Cords Integrates a seamless stainless steel tube internally, effectively shielding against aging-induced shrinkage and radial lateral pressure from the external polymer jacket. This maintains the geometric linearity of the internal fiber during long-term static conditions, significantly suppressing microbending loss: - [OFSCN® 2.0mm Micro Steel Armored Fiber Optic Patch Cord](https://www.ofscn.org/patch-cords/strong-01.html) ![OFSCN® 2.0mm Micro Steel Armored Fiber Optic Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/06d583d7b61478cbc87e8b7fab0502a6bdc373e8.jpeg) ![OFSCN® 2.0mm Micro Steel Armored Fiber Optic Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/c4f5c7c42f73224dc1b2375d81d32de5801427d6.jpeg) ![OFSCN® 2.0mm Micro Steel Armored Fiber Optic Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/1f3c896451b5c3ff1b05a16eac53983299651981.jpeg) #### 3. Steel Wire Rope Fiber Optic Patch Cords Utilizes an all-metal structure or multiple layers of high-strength steel wire rope combined with seamless stainless steel tubes for superior mechanical retention in environments with long-term self-weight suspension, vibration, or stress concentration, preventing micro-displacements at the connector tail end: - [OFSCN® 2.0mm Steel Wire Rope Fiber Optic Patch Cord](https://www.ofscn.org/patch-cords/strong-02.html) ![OFSCN® 2.0mm Steel Wire Rope Fiber Optic Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/0a72289bbb545f341c49823467e2dd990102733d.jpeg) ![OFSCN® 2.0mm Steel Wire Rope Fiber Optic Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/e843c8677fbf21498d9873ab15c0e0cce0729df3.jpeg) ![OFSCN® 2.0mm Steel Wire Rope Fiber Optic Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/cde4428c77c2f0ddf1988c13bf01e6c2e5de3317.jpeg) - [OFSCN® 3.0mm Steel Wire Rope Fiber Optic Patch Cord](https://www.ofscn.org/patch-cords/strong-03.html) ![OFSCN® 3.0mm Steel Wire Rope Fiber Optic Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/b3a40d08f5b484d8314df3518f18a5fa6dea2805.jpeg) ![OFSCN® 3.0mm Steel Wire Rope Fiber Optic Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/e778a674268c4c2c7766ec3625c93adfd98fdd05.jpeg) ![OFSCN® 3.0mm Steel Wire Rope Fiber Optic Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/ad19f41690f03273f74b7d7ad27a14e65949cf55.jpeg)