Exchange seal
If you have chosen to order your device with the option of a stainless steel front instead of an aluminum front, there is a silicone seal on the back of the unit to protect the connection section from moisture.
The seal may become porous after a long period of operation. In that case, you should replace the seal to continue protecting the connection section. You can order the following replacement seals from your Beckhoff sales department:
Ordering option  | Description  | 
|---|---|
C9900-Z520  | Replacement seals for stainless steel built-in Panel CP2x07-00x0 (C9900-F941)  | 
C9900-Z521  | Replacement seals for stainless steel built-in Panel CP2x13-00x0 (C9900-F942)  | 
C9900-Z522  | Replacement seals for stainless steel built-in Panel CP2x16-00x0 (C9900-F945)  | 
C9900-Z523  | Replacement seals for stainless steel built-in Panel CP2x18-00x0 (C9900-F946)  | 
C9900-Z524  | Replacement seals for stainless steel built-in Panel CP2x21-00x0 (C9900-F948)  | 
To replace the silicone seal, follow the steps shown below in figure 31:
- 1. Loosen and remove the M2.5x4 screws (section A).
 - 2. Remove the seal (section B).
 - 3. Place the new seal in the circumferential sealing groove on the back of the device (section C).
 - 4. Press along the seal with your fingers until it is neatly in the sealing groove. Make sure that the seal does not make any waves.
 - 5. Screw the seal back in place with the M2.5x4 screws.
 
- You have replaced the seal.