Non Standard JIS specs for GTZ14S generator battery, Opposite Polarity

Generator Battery Dilemma: GTZ14S Non JIS & YTZ14S JIS Standard

We came across an interesting find this week concerning a non JIS labeled GTZ14S generator battery. Never before had we come across a non JIS power sport sized sealed lead acid battery and were skeptical of what the customer was telling us. Sure enough, we found a picture of an off brand battery using the GTZ14S part number with opposite polarity in a BE9000 and BE6500 generator.

Japanese Industrial Standard (JIS)

The Japanese Industrial Standard or JIS has widely been used since the 1940’s and is THE known standard the world over for smaller automotive batteries such as power sport batteries. Since generators use small engines similar to motorcycles and ATV’s they typically get lumped into this category and use the same type of batteries.

What is the Difference in the GTZ14S Generator Battery?

The non JIS GTZ14S generator battery is the exact same size as the JIS Standardized battery. To prevent confusion we will refer to the standard JIS as the YTZ14S here on out. If you don’t already know, the Z14S is the standard and the YT or GT or PT or UT you may find in front is a way for different manufacturers to better be identified and build brand recognition. It is kind of like a call sign. But the Z14S informs us that the physical size and polarity of the battery should remain the same regardless the ‘call sign’ affixed in front. In the case of the non-standard GTZ14S the polarity has been flip-flopped. The positive terminal is on the right instead of the left!

What You Should Do If Your Generator Battery Needs Replacing

If you find yourself in the market for a new generator battery for your Honda, BE Pressure Supply or any other brand and are unsure about the whole battery thing, then do the following:

  1. 1. Write down the part number and brand (if available) of your existing battery.
  2. 2. Record the dimensions and polarity (which side is positive) of your existing battery.
  3. 3. Check to see if your generator cables are long enough to reach the opposite terminal or if you can place the battery in 180 degrees backwards and still have access to connect the generators cables to the terminals.
  4. 4. Log on to ImpactBattery.com or a site like BatteryLookup.com to match your brand and part number off their easy to use drop down menus.
  5. 5. Purchase with confidence the best battery based off your preference of longest warranty, lowest price, highest crank, amp hour, best overall value, etc.

Of course if you pulled out a GTZ14S and want a shortcut that we guarantee will be compatible, buy the MotoBatt MBTX9U. This battery is of the same dimensions but has 2 sets of terminals—one on each side—so you do not need to worry about standard / non-standard JIS polarity issue!

The Following Generators Use a GTZ14S or YTZ14S Battery

  • BE Pressure Supply: BE9000 and BE6500 watt Generators [85.571.095]
  • Honda: EM400S, EM5000S, EM6500S

Leave a comment if you know of some other generators that use the GTZ14S or YTZ14S battery so we can add it to the list.