Sorry maybe a silly question but...

I have the house DB TT install -  Ze at 0.38ohms with a high current 2 lead test.

Sub-board 35 meters away, with it's own earth stake. Zdb with a 3 lead low current test is 20.0 ohms.

All circuits off the sub board are relatively short and the Zs tests are around 20.0 - 21.1 ohms. 

Should the max Zs on the test cert be 1667? As electraform Zs test results are in red as the readings are above max Zs levels for the RCBO's 

TIA