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Inmate Phone

Inmate Phone

material:Cold-roll steel sheets

Inmate phone KNZD-27 Analogue
Inmate phone KNZD-27 VoIP

inmate phone

inmate phone KNZD-27

Inmate phone the family telephone management monitoring system for prison inmates phone affection develop professional monitoring system, strictly control the inmates can only immediate family calls, call process guards can monitor and control all the way, and in real time recording, later can query the recording and playback calls at any time.
The Inmate the family phone management system function is strong, high degree of automation, flexible control, security, make up the prison existing outside less family telephone number, the phone number, unable to control, monitor the inconvenience not recording, organization, inconvenience, etc, thoroughly eliminate the original pitfalls in the process of the family phone use. KNZD-27 is a professional telephone for inmate phone calls. prison phone calls usually need absolute strongest phone.People put money on phone for inmate to make phone calls inside the jail. KNTECH is professional communication system provider for inmate phone service. KNTECH manufacturing inmate telephone system include IP PBX and inmate phone.


1. Cold-roll steel body, vandal & tamper-resistant hardware, easy installation.
2. Waterproof rating IP55 dust proof.
3. Full keypad with memory, 10 button programmable telephone, support free dial.
4. Magnetic reed hook-switch.
5. Lightening protection to ITU-T recommendation K.21.
6. Heavy duty handset with hearing aid compatible receiver, noise canceling microphone.
7. Handset with industrial strong metal cord.
8. POE power supply or DC12V powered.
9. SUS keypad keep waterproof and dusty proof.
10. Temperature range from -40 degree to +70 degree.
11. Support echo cancellation.
12. Remote software upgrade, configuration and monitoring.
13. Optional 7 minute time out to release the line if the handset is left off hook. (This function upon buyer’s requirement).
14. Powder coated in UV stabilized polyester finish, gray white, blue, red, support OEM.
15. The housing covered with a layer of reflective label for easy identification at night. Optional
16. Application: Prison, bank, airport, school, metro, railway station, LRT, hotel, supermarket and pedestrian areas in cities etc.


inmate phone size


EN55022: emissions EN55024: immunity

Ingress Protection: GB4208-93 IP66 FCC ITU-T Recommendations K21

EMC: EN50121(Railway application-Electromagnetic Compatibility)


Unit size:280*210*60mm   Unit: N.W:2.6KG 

1pcs packing box size: 330*250*170mm Unit: N.W:2.6KG    Unit G.W:3KG 

6pcs in 1 outer Carton box: size: 730*390*340mm  N.W:31.8KG  G.W:34KG 

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==>>>> Product Specification

 SPECIFICATION - Analogue(Model NO.ZD0270012) 

1. PSTN analogue telephone

2. DTMF dialing

3. MTBF:100000hours

4. MTTR: 2 hours

5. Connection: RJ11 screw terminal pair cable

6. Applicable for various types of SPC exchange PABX and dispatching exchange system with feeding voltage of 33-60V.

 7. Ambient temperature:-30 ~ +60 degree. Relative humidity:10%~95% Atmospheric pressure: 86~106Kpa Circumstance noise:less than 60dB(A)

8. Sound level of ringing:over 70dB(A).

9. Standard frequency:low frequency group:697. 770. 852. 941Hz, high frequency group:1209. 1336. 1477Hz, frequency deviation:-1.5% ~ +1.5% 10.Call transmission index:(5KM)SLR<12,RLR<-1,STMR>

10, output impedance is 600 Ohm. maximum distance: 7KM

11.Connection: RJ11 screw terminal pair cable (or RJ11 Socket of plug upon request) with stainless

 SPECIFICATION - VoIP(Model NO.ZD0270022) 

1. VoIP SIP2.0 telephone                                              2. DTMF dialing                                                     

3. MTBF100000hours                                                   4. MTTR: 2 hours 

5. Auxiliary Contacts:1 Aux Output, dry contact            6. Rated load:0.3 A at 125 VAC; 1 A at 30 VDC

7. Contact Ratings. Load: Resistive load                      8. Echo cancellation code:G.167/G.168

9. Rated carry current:1A                                             10. Max.switching current:1A

11. Max.switching voltage:125 VAC,60VDC                 12. Audio Codes:G.711, G.722, G.729

13. IP Protocols:IPv4, TCP, UDP, TFTP, RTP, RTCP, DHCP, SIP

14. Free dial (maximum length of each number is 16 digits)            

15. Communication: Full duplex 2-way hands-free communication

16. Call Control Signaling:VOIP SIP Info(DTMF), RFC 2833(DTMF)

17. Network:10/100 BaseTX Ethernet, RJ45 connectors, Cat5e or better 

18. Power:Power over Ethernet, IEEE802.3af, Class 0  Local power, 12VDc,Idle 2W, Max 10W

19. Programming:Non-volatile flash memory programming and configuration through Web GUI

20. Management and Operation:DHCP and static IP, remote automatic software upgrade, centralized monitoring, status LED  

21. LAN Protocols:Power over Ethernet(PoE,802.3af), WLAN(IEEE 802.3af), Network Access Control(IEEE 802.1x),STP(IEEE 802.1d), RSTP(IEEE 802.1d-2004)

==>>>>Telephone System

Inmate Telephone Dispatching System

Inmate Telephone Dispatching System

==>>>>Product Application
Inmate phone applicationInmate phone application Inmate phone application 
Inmate phone application

==>>>>Product Detailed Pictures

Inmate Phone Detailed Picture

inmate phone
inmate phone inmate phone
inmate phone

==>>>>Product Video

==>>>>Please Email US marketing@koontech.com

This product model:KNZD-27