{"id":729,"date":"2026-06-03T00:58:52","date_gmt":"2026-06-03T00:58:52","guid":{"rendered":"https:\/\/planetary-gearboxes.com\/?p=729"},"modified":"2026-06-03T00:58:52","modified_gmt":"2026-06-03T00:58:52","slug":"planetary-gearbox-solar-tracker-selection","status":"publish","type":"post","link":"https:\/\/planetary-gearboxes.com\/nl\/planetary-gearbox-solar-tracker-selection\/","title":{"rendered":"Precision Planetary Gearbox for Solar Tracker Drives"},"content":{"rendered":"
\n

<\/p>\n

\n
\n
<\/div>\n
<\/div>\n
\n
Korea Ever-Power<\/span>
\nRenewable Energy Drive Guide<\/span><\/div>\n

Precision Planetary Gearbox for Solar Tracker Drives \u2014 Azimuth, Elevation, Wind Load, and Outdoor Lifetime Selection Guide<\/h1>\n

Solar tracker drives present a specification challenge unlike any other servo application: the normal tracking speed (0.0010 rpm) is so far below stable servo operating range that the ratio selection must be driven by the fast repositioning<\/em> speed, not by tracking speed. At the same time, 25-year outdoor lifetime in UV, humidity, salt spray, and temperature extremes demands IP65 and materials that most standard precision planetary gearboxes<\/a> are not specified for. This guide resolves both.<\/p>\n

Get Solar Tracker Specification Support \u2192<\/a><\/p>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

Two Challenges That Make Solar Tracker Drive Selection Unique<\/h2>\n

Solar tracker drives share some characteristics with standard servo positioning applications \u2014 but two engineering challenges are specific to solar tracking and are not covered adequately by standard servo drive selection methodology. Both must be understood before any ratio or frame size selection can be made correctly.<\/p>\n

\n
\n
Challenge 1: Tracking Speed Is Too Slow for Servo Motors<\/div>\n

A solar panel tracks the sun at 0.375\u00b0\/minute in azimuth \u2014 equivalent to 0.0010 rpm of the drive output shaft. Even through a 320:1 reduction, the motor would run at 0.33 rpm. Standard servo motors lose velocity control stability below approximately 50 rpm \u2014 entering a regime where encoder pulses arrive too infrequently for the velocity loop to operate. This means solar tracking speed itself cannot be used as the motor operating point.<\/strong> A completely different drive strategy is required.<\/p>\n

\n
Tracking: 0.0010 rpm output<\/div>\n
At i=320: motor = 0.33 rpm \u2190 unstable<\/div>\n
Solution: intermittent move-and-hold<\/div>\n<\/div>\n<\/div>\n
\n
Challenge 2: 25-Year Outdoor Exposure with No Maintenance Window<\/div>\n

Solar farms are typically designed for 25-year operating life with minimal on-site maintenance. A utility-scale solar park may have thousands of tracker drive units spread across a remote site in desert, coastal, or tropical conditions. Each unit must survive: UV radiation degrading seals and lubricant; salt spray in coastal installations; temperature cycles from \u221225\u00b0C night-time to +90\u00b0C summer housing temperature; dust and sand ingress in desert sites; and periodic rain-driven pressure washing in agricultural environments. IP65 and sealed-for-life lubrication are not optional \u2014 they are the minimum viable specification.<\/strong><\/p>\n

\n
Design life: 25 years (IEC 62446)<\/div>\n
Maintenance interval: ideally zero<\/div>\n
Sealed grease L10: 20,000h \u2248 7 years<\/div>\n
\u2192 Replace at 7-year service interval<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

Solar Tracking Motion Requirements \u2014 Azimuth, Elevation, and Emergency Stow<\/h2>\n

Solar tracker drives must execute three distinct motion profiles with very different speed and torque requirements. The gear ratio must accommodate all three simultaneously \u2014 which is why the fast repositioning speed, not the tracking speed, determines the practical upper limit on gear ratio.<\/p>\n

\n
\n
NORMAL
\nTRACKING<\/div>\n
\n
0.0010 rpm azimuth \u00b7 0.0007 rpm elevation \u00b7 continuous duty<\/div>\n

The sun traverses 180\u00b0 in approximately 8 hours (equatorial location, clear sky). At the drive output shaft: 0.375\u00b0\/min = 0.0010 rpm azimuth. Even through i=320:1, the motor speed would be 0.33 rpm \u2014 below stable servo range. Engineering solution: intermittent move-and-hold (see Module 3). The torque requirement is wind load torque divided by ratio \u2014 typically a modest motor in the 100W\u2013400W range at high ratio.<\/p>\n<\/div>\n<\/div>\n

\n
REPOSITIONING
\n\/ RESET<\/div>\n
\n
0.5\u20132.0 rpm output \u00b7 dawn east-to-west reset \u00b7 occasional<\/div>\n

At dawn, the tracker must move from the previous day’s west-facing stow position back to east-facing start \u2014 a 180\u00b0 azimuth reversal. At 1 rpm output through i=200, the motor runs at 200 rpm \u2014 well within stable servo range. This repositioning speed sets the upper<\/em> limit on gear ratio: at i=320 with n_fast=2 rpm, the motor would reach 640 rpm \u2014 still within range. The ratio should be selected such that fast repositioning gives n_motor between 100 and 1,500 rpm.<\/p>\n<\/div>\n<\/div>\n

\n
EMERGENCY
\nSTOW<\/div>\n
\n
Maximum speed \u00b7 triggered by wind alarm \u00b7 must complete within 3 minutes<\/div>\n

When wind speed exceeds the survival threshold (typically 25\u201330 m\/s), the controller commands emergency stow: panel moves to horizontal (minimum wind area) as fast as possible. IEC 62817 recommends stow completion within 3 minutes for most tracker designs. A 90\u00b0 stow travel at i=200 requires n_out = 90\/(3\u00d7360) = 0.083 rpm \u2192 n_motor = 16.7 rpm \u2014 slightly low but adequate for position-controlled stow. Select ratio such that stow motion completes reliably within the time budget at the motor’s rated torque.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

The Intermittent Tracking Strategy \u2014 Resolving the Motor Speed Paradox<\/h2>\n

The solution to the motor speed paradox is straightforward once identified: solar trackers do not need to move continuously<\/em> at tracking speed. They only need to maintain the panel within the required tracking accuracy tolerance. Instead of continuous slow rotation, the drive executes rapid small corrections at repositioning speed, separated by stationary hold periods. During the hold period, the motor is stopped (servo holding position with zero velocity command). During the correction, the motor runs at repositioning speed \u2014 well within stable servo range.<\/p>\n

\n
Intermittent Tracking: Calculation Example<\/div>\n
\n
Sun azimuth rate: 0.375\u00b0\/min (equatorial location, clear sky)<\/div>\n
Tracking tolerance: \u00b10.5\u00b0 (standard flat-panel PV)<\/div>\n
Correction interval = tolerance \/ sun_rate = 0.5\u00b0 \/ 0.375\u00b0\/min = 1.3 min<\/strong><\/div>\n
At 1 rpm repositioning speed: move 0.5\u00b0 in 0.5\u00b0\/(6\u00b0\/s) = 0.08 seconds<\/strong><\/div>\n
Motor during 0.08s move: 1 rpm \u00d7 i=200 = 200 rpm<\/strong> \u2705 stable servo range<\/div>\n
Motor during 1.3min hold: 0 rpm<\/strong> \u2705 no velocity loop issues<\/div>\n
For CPV \u00b10.1\u00b0 tolerance: correction every 0.3 min (16 seconds)<\/div>\n<\/div>\n
\n
\n
\u00b10.5\u00b0<\/div>\n
Flat panel PV<\/div>\n
Every 1.3 min<\/div>\n<\/div>\n
\n
\u00b10.1\u00b0<\/div>\n
CPV tracker<\/div>\n
Every 16 sec<\/div>\n<\/div>\n
\n
0.08s<\/div>\n
Duration per move<\/div>\n
at 1 rpm output<\/div>\n<\/div>\n
\n
200 rpm<\/div>\n
Motor during move<\/div>\n
at i=200<\/div>\n<\/div>\n<\/div>\n<\/div>\n
\n

Tracking accuracy and energy yield:<\/strong> The cosine effect of tracking inaccuracy reduces panel output by cos(\u03b8_error). At \u00b10.5\u00b0 tracking error, the power loss is only 0.0038% \u2014 for a 100kW array operating 2,920 hours per year, this is 11 kWh\/year, worth less than $1. Tracking accuracy to \u00b10.5\u00b0 is more than adequate for flat-panel PV from both an energy yield and gearbox specification perspective.<\/strong> CPV (concentrated photovoltaic) systems are the exception \u2014 they require \u00b10.1\u00b0 or better because their optical acceptance angle is much narrower.<\/p>\n<\/div>\n<\/section>\n

<\/p>\n

\"AFR<\/p>\n
Right-angle output planetary gearboxes are preferred for solar tracker elevation (tilt) axes where the motor must be positioned parallel to the panel mounting structure \u2014 an inline coaxial motor would protrude beyond the panel edge. The right-angle configuration routes the motor into the structural cavity, reducing the overall tracker assembly profile and simplifying weatherproofing. View EP series right-angle planetary gearbox configurations \u2192<\/a><\/div>\n<\/div>\n

<\/p>\n

\n

Wind Load Torque \u2014 The Primary Design Load for Solar Tracker Drives<\/h2>\n

The dominant torque load on a solar tracker drive is not the panel weight \u2014 it is wind pressure on the panel surface. Unlike most servo applications where inertia or friction defines the peak torque, solar trackers experience sustained aerodynamic loading that determines both the continuous rated torque and the emergency stow torque. Wind loading scales with the square of wind speed and linearly with panel area, making large multi-panel rows significantly more demanding than single-panel units.<\/p>\n

The torque formula: T_wind = 0.5 \u00d7 \u03c1_air \u00d7 v\u00b2 \u00d7 A_panel \u00d7 n_panels \u00d7 Cd \u00d7 R_arm, where \u03c1_air = 1.225 kg\/m\u00b3, A_panel = 2 m\u00b2 (400W panel), Cd = 1.0\u20131.5 (depends on array configuration), R_arm = 0.6 m (distance from rotation axis to panel centre of pressure).<\/p>\n

\n\n\n\n\n\n\n\n\n\n
Tracker Configuration<\/th>\nCd<\/th>\nT @ 15 m\/s
\ndesign wind<\/span><\/th>\n		T @ 20 m\/s
\nstrong wind<\/span><\/th>\n		T @ 25 m\/s
\nstow trigger<\/span><\/th>\n		T @ 30 m\/s
\nsurvival (stowed)<\/span><\/th>\n		With SF=2.0
\nDesign torque<\/span><\/th>\n<\/tr>\n<\/thead>\n
Single panel (1\u00d7400W)<\/td>\n1.0<\/td>\n165 N\u00b7m<\/td>\n294 N\u00b7m<\/td>\n459 N\u00b7m<\/td>\n662 N\u00b7m<\/td>\n588 N\u00b7m @ 20m\/s<\/td>\n<\/tr>\n
2-panel row<\/td>\n1.0<\/td>\n331 N\u00b7m<\/td>\n588 N\u00b7m<\/td>\n919 N\u00b7m<\/td>\n1,323 N\u00b7m<\/td>\n1,176 N\u00b7m @ 20m\/s<\/td>\n<\/tr>\n
4-panel (2\u00d72) \u2605 typical small farm<\/td>\n1.3<\/td>\n860 N\u00b7m<\/td>\n1,529 N\u00b7m<\/td>\n2,389 N\u00b7m<\/td>\n3,440 N\u00b7m<\/td>\n3,058 N\u00b7m @ 20m\/s<\/td>\n<\/tr>\n
10-panel row (5\u00d72) utility scale<\/td>\n1.4<\/td>\n2,315 N\u00b7m<\/td>\n4,116 N\u00b7m<\/td>\n6,431 N\u00b7m<\/td>\n9,261 N\u00b7m<\/td>\n8,232 N\u00b7m @ 20m\/s<\/td>\n<\/tr>\n
20-panel row (10\u00d72) large utility<\/td>\n1.5<\/td>\n4,961 N\u00b7m<\/td>\n8,820 N\u00b7m<\/td>\n13,781 N\u00b7m<\/td>\n19,845 N\u00b7m<\/td>\n17,640 N\u00b7m @ 20m\/s<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Wind torque T = 0.5 \u00d7 1.225 \u00d7 v\u00b2 \u00d7 2.0 \u00d7 Cd \u00d7 n_panels \u00d7 0.6m. Design torque = wind torque at 20 m\/s \u00d7 SF=2.0. For survival load (stow check), use T at 30 m\/s \u2014 gearbox must hold panel stationary with motor de-energised (worm gear) or with servo holding torque (planetary). Note: 10-panel and 20-panel row designs require multiple drive units along the row \u2014 these figures are per drive unit assuming equal load sharing.<\/p>\n

\n
Why the 4-panel config requires 3,058 N\u00b7m \u2014 and what that means for EP series selection<\/div>\n

A 4-panel (2\u00d72) tracker is the most common residential and small commercial solar farm configuration in Korea. At 20 m\/s wind with SF=2.0, the design torque is 3,058 N\u00b7m \u2014 which exceeds the rated output torque of all<\/em> standard single-stage EP-ZDE and EP-ZDS units. Two options are available: (1) use EP-ZDS-190 at 3-stage with rated output 1,800 N\u00b7m \u2014 only meets 59% of design torque at single unit; (2) use two drive units sharing the load, each carrying 1,529 N\u00b7m, which EP-ZDS-190 handles within its rating. For 4+ panel configurations, multi-drive or dedicated high-torque tracker drives are required. Korea Ever-Power application engineering provides multi-unit configuration guidance for these cases.<\/p>\n<\/div>\n<\/section>\n

<\/p>\n

\n

Backlash in Solar Tracking \u2014 What Matters and What Does Not<\/h2>\n

Backlash is frequently cited as a critical specification for solar tracker drives. In standard servo positioning \u2014 where the drive reverses direction frequently \u2014 backlash creates a dead band at each reversal that directly affects positioning accuracy. Solar tracking is fundamentally different: during the tracking day, the drive moves in only one direction (east to west). Backlash, being a direction-reversal phenomenon, has no effect on tracking accuracy during unidirectional motion.<\/p>\n

\n
\n
\u2705 During tracking (no direction reversal)<\/div>\n

Backlash has zero effect<\/strong> on tracking accuracy. The panel moves continuously in one direction \u2014 the gear mesh is always loaded on the same tooth flank. No dead band is engaged. A gearbox with 25 arcmin backlash tracks as accurately as one with 3 arcmin, assuming the drive is under load from wind.<\/p>\n<\/div>\n

\n
\u26a0 At dawn direction reversal<\/div>\n

When the drive reverses at dawn to reset from west-to-east, the backlash dead band must be traversed before the output shaft begins moving. At tracking speed (0.375\u00b0\/min), traversing 8 arcmin (0.133\u00b0) of backlash takes approximately 21 seconds. For standard flat-panel PV, this is negligible. For CPV systems needing \u00b10.1\u00b0 accuracy, even 8 arcmin = 0.133\u00b0 may briefly exceed tolerance during reversal.<\/p>\n<\/div>\n<\/div>\n

\n\n\n\n\n\n\n\n
Backlash Spec<\/th>\nDead Band at Reversal<\/th>\nTime to Traverse
\nat tracking speed<\/span><\/th>\n		During Tracking<\/th>\nSuitable For<\/th>\n<\/tr>\n<\/thead>\n
<8 arcmin (ZDE\/ZDS)<\/td>\n0.133\u00b0<\/td>\n~21 sec<\/td>\nNo effect \u2705<\/td>\nAll flat-panel PV, CPV with dawn compensation<\/td>\n<\/tr>\n
<12 arcmin (2-stage)<\/td>\n0.200\u00b0<\/td>\n~32 sec<\/td>\nNo effect \u2705<\/td>\nAll flat-panel PV applications<\/td>\n<\/tr>\n
<25 arcmin (ZDWE\/ZDWF)<\/td>\n0.417\u00b0<\/td>\n~67 sec<\/td>\nNo effect \u2705<\/td>\nFlat-panel only; too wide for CPV tracking<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
\n

Specification implication:<\/strong> For standard flat-panel solar farms, backlash is not a meaningful selection criterion beyond ensuring a minimum quality level. The standard EP-ZDE\/ZDS (<8 arcmin) or even a lower-cost unit with <25 arcmin is technically adequate from a tracking accuracy standpoint. The specification criteria that actually matter for solar tracker drives are: (1) wind load torque capacity<\/strong>, (2) IP65 for outdoor lifetime<\/strong>, (3) gear ratio for servo stability during repositioning<\/strong>, and (4) temperature range for the deployment climate<\/strong>. Backlash is a secondary parameter \u2014 specify <8 arcmin for quality assurance, not because it is the limiting accuracy constraint.<\/p>\n<\/div>\n<\/section>\n

<\/p>\n

\"Planetary<\/p>\n
EP series precision planetary gearboxes are deployed in single-axis and dual-axis photovoltaic tracker systems across Korean and Asian solar installations. The combination of IP65 sealing, sealed-for-life PAO lubrication, \u221225\u00b0C to +90\u00b0C operating range, and 20,000h L10 bearing life addresses the primary longevity challenges of outdoor solar tracker drives.<\/div>\n<\/div>\n

<\/p>\n

\n

Outdoor Environment Requirements \u2014 IP Rating and Temperature by Deployment Zone<\/h2>\n

The deployment environment of a solar tracker determines the minimum IP rating and material requirements for the drive gearbox. Solar farms span nearly every climatic zone \u2014 from Korean coastal regions with salt spray to desert installations with extreme UV and dust to tropical installations with high humidity and frequent rain. The 25-year design life requirement (IEC 62446) means no component can be considered “too expensive to specify correctly” at initial design.<\/p>\n

\n
Deployment EnvironmentIP Min.<\/span>Recommended EP<\/span><\/div>\n
\n
\n
Inland temperate \u2014 Korean standard (Seoul, Daejeon)<\/div>\n
Annual rain, moderate humidity, temperatures \u221215\u00b0C to +40\u00b0C. No salt. Standard Korean solar farm deployment. Sealed lubrication survives 7-year maintenance interval.<\/div>\n<\/div>\n
IP54<\/div>\n
EP-ZDE-160
\nEP-ZDS-115<\/div>\n<\/div>\n
\n
\n
Korean coastal (Busan, Incheon, Jeju) \u2014 salt spray<\/div>\n
Salt-laden air accelerates corrosion on aluminium housings and zinc-plated fasteners. Direct salt fog exposure requires IP65 to prevent chloride ingress into grease cavity. Anodised aluminium housing adequate for indirect exposure.<\/div>\n<\/div>\n
IP65<\/div>\n
EP-ZDS-115\/142<\/div>\n<\/div>\n
\n
\n
Desert (Middle East, Central Asia, Australian Outback)<\/div>\n
Extreme UV, sand ingress, temperature +80\u00b0C in summer (housing may reach +90\u00b0C). EP series rated to +90\u00b0C housing temperature. Dust storm sand load on seals \u2014 IP65 dust-tight seal critical. Annual cleaning recommended to avoid abrasive seal wear.<\/div>\n<\/div>\n
IP65<\/div>\n
EP-ZDS-115\/142<\/div>\n<\/div>\n
\n
\n
Tropical (Southeast Asia, equatorial Africa) \u2014 high humidity<\/div>\n
Relative humidity consistently above 80%, frequent rain, high temperature. Condensation cycling degrades IP54 seals. Fungal growth possible in non-IP65 cable entries. IP65 required throughout. Consider stainless fasteners for tropical corrosion rates.<\/div>\n<\/div>\n
IP65<\/div>\n
EP-ZDS series<\/div>\n<\/div>\n
\n
\n
Cold climate (Mongolia, northern China, Korea winter)<\/div>\n
Operating temperatures to \u221225\u00b0C. EP series rated \u221225\u00b0C minimum with PAO grease. Below \u221225\u00b0C: non-standard; specify cold-start protocol. Freeze-thaw cycling stresses seals \u2014 IP65 reduces water ingress during snowmelt. Recommend reduced-load warm-up at startup below \u221215\u00b0C.<\/div>\n<\/div>\n
IP54+<\/div>\n
EP-ZDE\/ZDS
\n(PAO grease)<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\n

EP Series Selection for Four Solar Tracker Configurations<\/h2>\n

The four primary solar tracker configurations used in Korean and Asian solar installations have distinct drive requirements determined by panel count (wind load), tracking accuracy requirement (flat PV vs CPV), axis count (single vs dual), and deployment scale (residential to utility).<\/p>\n

<\/p>\n

\n
\n
CONFIG 1<\/div>\n
Single-Axis, 1\u20132 Panels \u2014 Small Farm \/ Agrivoltaic<\/div>\n<\/div>\n
\n
Requirements:<\/strong>
\nT_design \u2264 600 N\u00b7m (1-panel at 20m\/s, SF=2.0)
\nn_output_fast \u2264 2 rpm
\nTracking: \u00b10.5\u00b0 adequate
\nIP54 (inland) or IP65 (coastal)<\/div>\n
Ratio selection:<\/strong>
\nT_motor = 588\/(200\u00d70.90) = 3.3 Nm
\n\u2192 400\u2013750W servo motor
\ni=200: n_motor@2rpm = 400rpm \u2705
\n\u2192 i=160\u2013200 recommended<\/div>\n
Recommended:<\/strong>
\nEP-ZDE-160, 160:1<\/a> (IP54)
\nor EP-ZDS-115, 160:1 (IP65, coastal)
\nT_ceiling: 450\/210 N\u00b7m \u2705 vs 588 Nm design<\/div>\n<\/div>\n<\/div>\n

<\/p>\n

\n
\n
CONFIG 2<\/div>\n
Single-Axis, 2\u20134 Panels \u2014 Commercial \/ Mid-Scale<\/div>\n<\/div>\n
\n
Requirements:<\/strong>
\nT_design 1,176\u20133,058 N\u00b7m (SF=2.0 @ 20m\/s)
\nIP65 recommended (outdoor 25yr)
\nn_output_fast \u2264 1.5 rpm
\nTracking: \u00b10.5\u00b0 adequate<\/div>\n
Ratio \/ torque:<\/strong>
\n2-panel: T_design=1,176Nm \u2192 EP-ZDS-142 \u2705
\n4-panel: T_design=3,058Nm \u2192 2\u00d7 drives
\ni=160\u2013200, n_motor@1.5rpm=240\u2013300rpm \u2705<\/div>\n
Recommended:<\/strong>
\n2-panel: EP-ZDS-142, 160:1, IP65<\/a>
\n4-panel: 2\u00d7 EP-ZDS-142 sharing load
\nor 1\u00d7 EP-ZDS-190 (1,800Nm ceiling, 3-stage)<\/div>\n<\/div>\n<\/div>\n

<\/p>\n

\n
\n
CONFIG 3<\/div>\n
Dual-Axis CPV \u2014 High-Accuracy Concentrated Photovoltaic<\/div>\n<\/div>\n
\n
Requirements:<\/strong>
\nAzimuth + elevation axes (2 drives)
\nTracking accuracy: \u00b10.1\u00b0 (CPV optical acceptance)
\nCorrection every 16 seconds
\nIP65 mandatory (outdoor, high-value target)
\nT: 200\u2013800 N\u00b7m per axis at design wind<\/div>\n
Ratio selection:<\/strong>
\nAzimuth i=200\u2013256 (motor stable @ 200\u2013256rpm fast)
\nElevation i=120\u2013160 (lower speed range)
\nBL <8 arcmin \u2192 CPV reversal OK with controller compensation<\/div>\n
Recommended:<\/strong>
\nAzimuth: EP-ZDS-115\/142, 200:1, IP65
\nElevation: EP-ZDS-115, 120:1, right-angle (ZDWF)
\nBoth: BL <8 arcmin, FKM seals for outdoor<\/div>\n<\/div>\n<\/div>\n

<\/p>\n

\n
\n
CONFIG 4<\/div>\n
Parabolic Trough Concentrator \u2014 Large CSP Azimuth Drive<\/div>\n<\/div>\n
\n
Requirements:<\/strong>
\nVery high torque: 500\u20131,800 N\u00b7m per drive unit
\nAzimuth only (trough tracks E-W daily)
\nHousing temperature risk: proximity to hot trough may exceed +90\u00b0C
\nIP65 essential; FKM seals mandatory
\nVerify thermal isolation from collector structure<\/div>\n
Torque \/ ratio:<\/strong>
\nDesign torque: 500\u20131800 Nm
\nEP-ZDS-142 ceiling: 910 Nm \u2705 (medium CSP)
\nEP-ZDS-190 ceiling: 1,800 Nm \u2705 (large CSP)
\nRatio: 100\u2013160:1 (higher output speed needed)<\/div>\n
Recommended:<\/strong>
\nMedium CSP: EP-ZDS-142, 120:1, IP65, FKM<\/strong>
\nLarge CSP: EP-ZDS-190, 100:1, IP65, FKM
\n\u26a0 Verify housing temp \u2264 90\u00b0C in proximity to collector<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

\"AFHK<\/p>\n
Compact right-angle planetary gearbox configurations are particularly suited to dual-axis CPV solar tracker elevation drives where mounting space is constrained by the concentrating optics assembly. High reduction ratios (120:1 to 256:1) in a compact housing, combined with IP65 outdoor sealing and FKM seals for chemical resistance, provide the complete specification for CPV tracker elevation axis drives in utility-scale installations. Contact Korea Ever-Power application engineering for dual-axis CPV system configuration support.<\/div>\n<\/div>\n

<\/p>\n

\n

Solar Tracker Drive Specification Checklist \u2014 Six Parameters Before Ordering<\/h2>\n
\n
\n
01<\/div>\n
Wind Load Torque \u2014 Primary Design Load<\/div>\n

Calculate T_wind at design wind speed (typically 20 m\/s for operating, 30 m\/s for survival). Apply SF=2.0. Determine panel count per drive unit. Use the wind torque table in Module 4 to find T_design. Verify against EP series output torque ceiling for selected frame and ratio.<\/p>\n<\/div>\n

\n
02<\/div>\n
Gear Ratio \u2014 Driven by Repositioning Speed<\/div>\n

Set i such that n_motor at fast repositioning (1\u20132 rpm output) gives 100\u2013600 rpm. Check n_motor at max repositioning \u2264 3,000 rpm. Use intermittent tracking strategy \u2014 do not attempt to run motor at tracking speed continuously. Recommended range: i=120\u2013256 for most solar tracker configurations. See the high-ratio guide<\/a> for detailed analysis.<\/p>\n<\/div>\n

\n
03<\/div>\n
IP Rating \u2014 Deployment Zone<\/div>\n

IP54 minimum for inland temperate (standard Korean inland site). IP65 mandatory for coastal, desert, tropical, and agricultural sites. Specify FKM seals for any outdoor installation \u2014 standard NBR degrades under UV and ozone exposure. IP65 = EP-ZDS series only.<\/p>\n<\/div>\n

\n
04<\/div>\n
Temperature Range \u2014 Housing Temperature Budget<\/div>\n

Verify housing temperature \u2264 +90\u00b0C. In direct sun with poor ventilation, dark-coloured gearbox housings in desert can approach 85\u201390\u00b0C in summer. For CSP\/trough systems, thermal isolation from hot collector structure is essential. EP series rated \u221225\u00b0C min; for colder climates, specify cold-start protocol.<\/p>\n<\/div>\n

\n
05<\/div>\n
Tracking Accuracy \u2014 Flat PV vs CPV<\/div>\n

For flat-panel PV: \u00b10.5\u00b0 tolerance is adequate; backlash up to 25 arcmin acceptable from tracking accuracy standpoint. For CPV: \u00b10.1\u00b0 or better; specify <8 arcmin and implement controller backlash compensation at dawn reversal. Accuracy during tracking (unidirectional) is not backlash-limited for either type.<\/p>\n<\/div>\n

\n
06<\/div>\n
Service Interval Planning \u2014 7-Year Gearbox Replacement<\/div>\n

EP series sealed grease has L10 = 20,000 hours \u2248 7 years at 2,920 hours\/year operating time. For a 25-year solar farm design life, plan for two gearbox replacements (at year 7 and year 14). Include replacement cost in LCOE calculation. Stocking spare units in bulk reduces per-unit replacement cost; confirm Korean distributor availability before commissioning large solar farms.<\/p>\n<\/div>\n<\/div>\n<\/section>\n


\n<\/span><\/p>\n

\n
\n
\n
Specifying EP Series for a Solar Tracker Installation?<\/div>\n

Korea Ever-Power provides solar tracker drive specifications including wind load torque calculation for your specific panel configuration, gear ratio recommendation for stable servo operation, IP rating assessment by deployment zone, and housing temperature verification. Provide panel count, wind speed design point, deployment location, and tracker type (single\/dual axis, PV\/CPV) for a complete EP series recommendation.<\/p>\n<\/div>\n

Request Solar Tracker Specification \u2192<\/a><\/p>\n
sales@planetary-gearboxes.com<\/div>\n<\/div>\n<\/div>\n

<\/p>\n

\n
EP Series for Solar Tracker Drive Applications<\/div>\n
\n
\n
EP-ZDS Series<\/div>\n
Commercial\/utility solar, all coastal\/desert\/tropical<\/strong> \u00b7 IP65 \u00b7 up to 1,800 N\u00b7m \u00b7 FKM seals \u00b7 \u221225\u00b0C to +90\u00b0C \u00b7 3-stage 60\u2013516:1<\/div>\n

View specifications \u2192<\/a><\/p>\n<\/div>\n

\n
EP-ZDE Series<\/div>\n
Small farm \/ inland \/ residential solar<\/strong> \u00b7 IP54 \u00b7 up to 800 N\u00b7m \u00b7 3-stage 60\u2013516:1 \u00b7 90% efficiency \u00b7 sealed for life<\/div>\n

View specifications \u2192<\/a><\/p>\n<\/div>\n

\n
EP-ZDWF Series<\/div>\n
CPV elevation axis, dual-axis compact<\/strong> \u00b7 right-angle output \u00b7 IP54 \u00b7 motor parallel to structure \u00b7 saves space in tilt axis assembly<\/div>\n

View specifications \u2192<\/a><\/p>\n<\/div>\n<\/div>\n

Browse all planetary gearboxes \u2192<\/a><\/div>\n<\/div>\n<\/section>\n

Redacteur: Cxm<\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"

Korea Ever-Power Renewable Energy Drive Guide Precision Planetary Gearbox for Solar Tracker Drives \u2014 Azimuth, Elevation, Wind Load, and Outdoor Lifetime Selection Guide Solar tracker drives present a specification challenge unlike any other servo application: the normal tracking speed (0.0010 rpm) is so far below stable servo operating range that the ratio selection must be […]<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[965],"tags":[],"class_list":["post-729","post","type-post","status-publish","format-standard","hentry","category-application-and-technical-guid"],"_links":{"self":[{"href":"https:\/\/planetary-gearboxes.com\/nl\/wp-json\/wp\/v2\/posts\/729","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/planetary-gearboxes.com\/nl\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/planetary-gearboxes.com\/nl\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/nl\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/nl\/wp-json\/wp\/v2\/comments?post=729"}],"version-history":[{"count":1,"href":"https:\/\/planetary-gearboxes.com\/nl\/wp-json\/wp\/v2\/posts\/729\/revisions"}],"predecessor-version":[{"id":730,"href":"https:\/\/planetary-gearboxes.com\/nl\/wp-json\/wp\/v2\/posts\/729\/revisions\/730"}],"wp:attachment":[{"href":"https:\/\/planetary-gearboxes.com\/nl\/wp-json\/wp\/v2\/media?parent=729"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/nl\/wp-json\/wp\/v2\/categories?post=729"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/planetary-gearboxes.com\/nl\/wp-json\/wp\/v2\/tags?post=729"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}