• As of October 1, 2008, our U.S. business is called Siemens Energy, Inc.

Medium-voltage TechTopics is a series of papers that discuss issues of interest to users or specifiers of medium-voltage electrical equipment, including

Topics discussed in medium-voltage TechTopics will include application, selection and discussion of the applicable standards for these products. Medium-voltage TechTopics issues will be added to address recurring questions.

TechTopics No. 01 - Surge limiter application recommendations for metal-clad switchgear up to 15 kV (116 KB)

TechTopics No. 02 - Loss of vacuum (107 KB)

TechTopics No. 03 - Vacuum vs. SF₆ (113 KB)

TechTopics No. 04 - kA rated circuit breakers and switchgear (140 KB)

TechTopics No. 05 - Reclosing applications - minimum reclosing time (112 KB)

TechTopics No. 06 - Three-cycle versus five-cycle interrupting time (122 KB)

TechTopics No. 07 - Current transformers - Use of 600 V CT's in metal-clad switchgear (128 KB)

TechTopics No. 08 - Heat generation estimation for type GM switchgear (up to 15 kV) (144 KB)

TechTopics No. 09 - Heat generation estimation for type GM38 switchgear (up to 38 kV) (144 KB)

TechTopics10Rev0 - Heat generation estimation for Series 81000^TM controllers (65 KB)

TechTopics11Rev0 - Fast bus transfer times for GMI circuit breakers (77 KB)

TechTopics13Rev0 - Use of latched contactors to switch transformers (60 KB)

TechTopics14Rev0 - X-radiation emissions by vacuum interrupters (83 KB)

TechTopics15Rev0 - Expected life of electrical equipment (97 KB)

TechTopics16Rev0 - Bus joint fundamentals (76 KB)

TechTopics17Rev0 - Main bus continuous current ratings (85 KB)

TechTopics18Rev1 - Bus joint and primary disconnect plating (73 KB)

TechTopics19Rev0 - Bus joint current density (56 KB)

TechTopics20Rev0 - Power factor correction capacitor - Sizing for motors (402 KB)

TechTopics21Rev0 - "Bus bracing" in metal-clad switchgear (81 KB)

TechTopics22Rev0 - "Bus bracing" in metal-enclosed switchgear (90 KB)

TechTopics23Rev2 - Circuit breaker ratings - GMI circuit breakers (258 KB)

TechTopics24Rev0 - Checking integrity of vacuum interrupters (60 KB)

TechTopics25Rev0 - Shunt reactor switching applications (59 KB)

TechTopics26Rev0 - Ground bus ratings (51 KB)

TechTopics27Rev0 - Standards for medium-voltage metal-clad switchgear (97 KB)

TechTopics28Rev0 - Standards for outdoor high-voltage circuit breakers (94 KB)

TechTopics29Rev0 - Derating factors for reclosing service (68 KB)

TechTopics30Rev0 - Altitude correction factors (115 KB)

TechTopics31Rev0 - Solar radiation correction factors (67 KB)

TechTopics32Rev1 - Capacitor switching applications (60 KB)

TechTopics34Rev0 - Three-cycle vs. five-cycle interrupting time - 3AK1 circuit breakers (75 KB)

TechTopics35Rev0 - Transient recovery voltage (94 KB)

TechTopics36Rev0 - Early 'b' contacts (47 KB)

TechTopics37Rev0 - Low current switching capabilities (82 KB)

TechTopics38Rev0 - Harmonic filter applications (68 KB)

TechTopics39Rev0 - Heat generation estimation for Type NXAIR P switchgear (up to 15 kV) (110 KB)

TechTopics41Rev0 - Circuit breakers or switches - Application considerations (23 KB)

TechTopics42Rev0 - Circuit breakers or contactors - Application considerations (24 KB)

TechTopics43Rev0 - Interposing relay requirements (34 KB)

TechTopics44Rev1 - Anatomy of a short-circuit (161 KB)

TechTopics45Rev0 - Accuracy of CTs used in medium-voltage control equipment (53 KB)

TechTopics46Rev0 - Selection of current transformer ratio in medium-voltage control (67 KB)

TechTopics47Rev0 - 7.2 kV equipment basic insulation levels (BIL) (88 KB)

TechTopics48Rev0 - Fan-cooling control circuit for forced-air cooled circuit breakers (89 KB)

TechTopics50Rev0 - Ground sensor current transformer cable routing (107 KB)

TechTopics52Rev0 - Insulation of switchgear terminations (78 KB)

TechTopics53Rev0 - Use of SF₆ gas in medium-voltage switchgear (122 KB)

TechTopics54Rev0 - Interrupter switch technology comparison - Simosec SF₆ switch vs. conventional air switches (135 KB)

TechTopics55Rev0 - Capacitor trip devices (73 KB)

TechTopics56Rev0 - Switchgear outdoor enclosure type - Why isn't it NEMA 3? (64 KB)

TechTopics57Rev0 - Arc-flash hazard labels (117 KB)

TechTopics58Rev0 - What is the difference between E-rated and R-rated current-limiting fuses? (93 KB)

TechTopics59Rev0 - Control power sources for switchgear (76 KB)

TechTopics60Rev0 - Use of cable for connections in medium-voltage switchgear (72 KB)

TechTopics61Rev1 - Circuit breaker "standard duty cycle" (89 KB)

TechTopics62Rev0 - A bit of history on circuit breaker standards (28 KB)

TechTopics63Rev0 - Recovery of SF₆ gas from Simosec switches at end-of-life condition (92 KB)

TechTopics64Rev0 - NFPA 70E - Changes expected in 2009 edition (35 KB)

TechTopics No. 65 - Arc furnace switching applications (127 KB)

TechTopics No. 66 - Clearances (135 KB)

TechTopics No. 67 - %dc component (151 KB)

TechTopics No. 68 - Heat generation estimation for historic switchgear type D (to 4.76 kV) and type F (to 15 kV) with air magnetic circuit breakers (128 KB)

TechTopics No. 69 - Fast bus transfer times for GMSG circuit breakers (113 KB)

TechTopics No. 70 - Arc-resistant switchgear accessibility types (127 KB)

TechTopics No. 71 - Generator circuit breakers (126 KB)

TechTopics No. 72 - Generator circuit breaker applications - delayed current zeroes (147 KB)

TechTopics No. 73 - Generator circuit breaker applications - transient recovery voltages (128 KB)

TechTopics No. 74 - Heat generation estimation for type GM-SG switchgear (up to 15 kV) (138 KB)

TechTopics No. 75 - Ferroresonance in ungrounded systems with voltage transformers connected line-to-ground (143 KB)

TechTopics No. 76 - Heat generation estimation for type Simosec load interrupter switchgear (132 KB)