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Max Zs Values also includes the 80% temperature adjusted values and a some MCCB 60947-2 manufacture Zs charts.
- 100% BS 7671 Zs Values
- 80% On Site Guide Zs Values
- 0.4 (s) second disconnection times
- 0.2 (s) second disconnection times
- 5 (s) second disconnection times
- Common BS EN Devices:
Scroll through the list of protective devices and select the device rating to calculate the maximum permitted Zs value for your selected protective device and rating combination.
- 60947-2 MCCB's Zs Tables:
Look up the maximum permitted Zs tables for a selection of MCCB manufacture devices (some).
- Maximum Zs Features:
+ Maximum Disconnection Times
+ BS 7671 18th Edition Zs Tables
+ Fuse's
+ MCB's
+ RCBO's
+ RCD's in TT earthing systems
+ Max REC Ze values
+ 100% values
+ 80% values
+ 0.4 second disconnection times
+ 0.2 second disconnection times
+ 5 second disconnection times
+ Uo 55v (U 110v) single phase and Uo 63.5v (three
phase) Zs values
+ BS EN 60947-2 MCCB manufacture device charts
(some)
There is now a new \"Zs Converter\" to convert old Zs values to the new 18th edition 230v Cmin Zs values.
Check out our collection of electrical apps such as the \"Pro Certs\" Electrical Certification App for iPad.","app_summary":"'Max Zs Values', published by a United Kingdom-based company. The app was last updated on 29 July 2025. Released in United Kingdom on 12 February 2012 and globally on 12 February 2012. 'Max Zs Values' belongs to the 'Reference' category maintaining a content rating of '4+'. In United Kingdom, 'Max Zs Values' ranked 132nd on the 'Top Grossing iPhone Apps' chart in the 'Reference' category. Last month's estimates were < 5k downloads and < $5k revenue. The app is available in United Kingdom, US, and Australia but not being advertised actively. Sign up / Sign in to learn more about the time spent, session durations, usage & engagement (DAU, WAU, MAU), retention, churn, marketshare, growth trends, and other market statistics.","subtitle":"Zs Values 18th Edition BS 7671","promo_text":"A comprehensive database of maximum Zs values for fuses, MCB's, RCBO's, and RCD's. Also includes many manufacturer MCCB BS EN 60947-2 and ACB maximum Zs tables."},"has_in_app_purchases":false,"installs":null,"language":"EN","support_url":"https://www.procertssoftware.com/contact/","top_countries":["GB","US","AU"],"valid_countries":["AE","AO","AR","AT","AU","AZ","BE","BF","BG","BH","BJ","BO","BR","BY","CA","CG","CH","CI","CL","CM","CN","CO","CR","CY","CZ","DE","DK","DO","DZ","EC","EE","EG","ES","FI","GB","GE","GH","GR","GT","HK","HR","HU","ID","IE","IL","IN","IQ","IT","JO","JP","KE","KH","KR","KW","KZ","LA","LB","LK","LT","LU","LV","LY","MA","ML","MM","MO","MT","MX","MY","MZ","NG","NI","NL","NO","NZ","OM","PA","PE","PH","PK","PL","PT","PY","QA","RO","RS","RU","SA","SE","SG","SI","SK","SN","SV","TH","TN","TR","TW","TZ","UA","UG","US","UY","UZ","VE","VN","YE","ZA","ZM","ZW"],"available_countries":["US","AU","CA","CN","FR","DE","GB","IT","JP","KR","RU","DZ","AO","AR","AT","AZ","BB","BY","BE","BM","BR","BG","CL","CO","CR","HR","CZ","DK","DO","EC","EG","SV","FI","GH","GR","GT","HK","HU","IN","ID","IE","IL","KZ","KE","KW","LB","LT","LU","MO","MG","MY","MX","NL","NZ","NG","NO","OM","PK","PA","PE","PH","PL","PT","QA","RO","SA","SG","SK","SI","ZA","ES","LK","SE","CH","TW","TH","TN","TR","UA","AE","UY","UZ","VE","VN","BO","EE","LV","NI","PY","KH","AF","GE","IQ","LY","MA","MZ","MM","YE","BH","CY","MT","RS","BJ","BF","CM","CG","CI","JO","LA","ML","SN","TZ","UG","ZM","ZW"],"pre_order_countries":[],"website_url":"https://www.procertssoftware.com/max-zs-values/","app_id":498838137,"app_view_url":"/ios/gb/pro-certs-software-ltd/app/max-zs-values/498838137/","country":"GB","icon_url":"https://is1-ssl.mzstatic.com/image/thumb/Purple221/v4/86/4f/83/864f8382-044b-59ef-5a8e-0dd6eb261560/AppIcon-1x_U007emarketing-0-11-0-0-85-220-0.png/150x150bb.jpg","name":"Max Zs Values","os":"ios","price":{"currency":"GBP","value":999,"string_value":"£9.99","subunit_to_unit":100},"publisher_id":444429696,"publisher_name":"Pro Certs Software Ltd","publisher_profile_url":"/publisher/ios/444429696","rating":4.2,"rating_breakdown":[3,0,0,4,13],"rating_count":20,"country_release_date":1329058980000,"current_version":"3.1.18","file_size":15792128,"first_released_in":["US","AU","CA","CN","FR","DE","GB","IT","JP","KR","RU","DZ","AO","AR","AT","AZ","BB","BY","BE","BM","BR","BG","CL","CO","CR","HR","CZ","DK","DO","EC","EG","SV","FI","GH","GR","GT","HK","HU","IN","ID","IE","IL","KZ","KE","KW","LB","LT","LU","MO","MG","MY","MX","NL","NZ","NG","NO","OM","PK","PA","PE","PH","PL","PT","QA","RO","SA","SG","SK","SI","ZA","ES","LK","SE","CH","TW","TH","TN","TR","AE","UY","UZ","VE","VN","BO","EE","LV","NI","PY","YE","BH","CY","MT","JO","ML","SN","TZ","UG"],"minimum_os_version":"11.0","publisher_country":"United Kingdom","recent_release_date":1753747200000,"release_date":1329058980000,"release_status":"REGIONAL_RELEASE","supported_languages":["EN"],"worldwide_release_date":1329004800000,"store_removal_date":null,"cohort_id":null,"worldwide_last_month_revenue":{"unit":"cent","type":"currency","currency":"USD","value":100000},"worldwide_last_month_downloads":{"unit":"unit","type":"integer","value":1000},"category_rankings":{"app_id":498838137,"country":"GB","ipad":{"top_free":null,"top_grossing":null,"top_paid":{"all_categories":null,"primary_categories":[{"6006":133}],"sub_categories":[]}},"iphone":{"top_free":null,"top_grossing":{"all_categories":null,"primary_categories":[{"6006":null}],"sub_categories":[]},"top_paid":{"all_categories":null,"primary_categories":[{"6006":10}],"sub_categories":[]}}}}