URM37 sensor controlling servo issue (pin5)

Hi everybody,

I'm using the URM27 sensor with an arduino Uno.
In order to avoid servo control done by my arduino card I'm trying to use pin 5 of this sensor.
The URM37 pin 5 seems to be :

5. MOTO - Servo control signal output.

So I connected my servo motor to this pin and asked arduino to get Measurement to a specific position.
I use Arduino URMSerial library.

Everything works fine but it seems that servo angle positionning (using this 5 pin) is half of due angle ?!
For example, asking for angle 180° will only move to 90°.
It seems 180 angle steps (called in a loop) only actually move my servo from 0 to 90°.

Please escuse my poor english (I hope someone will understand me)

Can somebody help ?

Thanks