Yealink SIP- T28P User Manual

Enterprise IP Phone Trouble Shooting
Trouble Shooting
I can not register to the server？
1) Check the IP address. If you set your WAN port in DHCP mode, please make sure
that your DHCP server is on.
2) Check your gateway.
3) Check your DNS server.
4) Make sure your account information is the same as you have got from your ISP.
5) Check whether the SIP server is on.
6) Check the SIP register port, the default value is 5060.
I can’t get the IP address?
1) Make sure you have plugged the Ethernet cable into the WAN port.
2) Make sure that the DHCP server is on, and there are available IP addresses in the
server.
3) Try to set your WAN port to static IP client mode.
During a call, I can not hear any voice?
1) Make sure your handset is tightly connected with the phone.
2) Check whether you have muted the conversation or not.
3) Consult the outbound server details with your ISP.
Have DTMF problem?
1) Check which kind of DTMF you are using, and whether it is compatible with the
server.
2) Consult the payload value with your ISP.
How to change the time?
Select the time zone or enter the time information manually on the webpage or the
phone.
How to answer the incoming calls during a call?
If a call comes in when you are in a conversation, press the Answer key to answer the
incoming call.
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Yealink SIP- T28P Specifications

General

Expansion module support	Yes
Ethernet LAN (RJ-45) ports	2
Keypad number of keys	48
Voice codecs	G.711, G.722, G.723.1, G.726
Handset type	Wired handset
Product type	IP Phone
Product color	Black
Touchscreen	-
Display resolution	320 x 160 pixels
Lines quantity	- lines
Phonebook capacity	- entries
Number of VoIP accounts	6
Bluetooth	No
Security algorithms	HTTPS, SSL/TLS
AC adapter input voltage	100 - 240 V
AC adapter output voltage	5 V
Power consumption (typical)	2.6 W
Operating relative humidity (H-H)	10 - 95 %
Compliance industry standards	IEEE 802.3af
Number of handles included	1 pc(s)

Weight and Dimensions

Depth	204 mm
Width	273 mm
Height	42 mm
Weight	1050 g