ST220安全智能查线仪是在普通电话机的基础上，增加了障碍测试、自主振铃、呼叫用户、对线、高压保护和高压验电等功能，有效地降低了线路维护人员的工作量，坚固耐用是线路维护人员开通和维护相关业务的理想工具。 

功能简介 

1、 电话机功能：同普通电话机一样，接于电话线上，具有拨号、通话、收铃功能。

2、 障碍测试功能：将测试线接于无源待测用户线上，可进行绝缘测试、地气测试和断线测试。

3、 呼叫用户和对讲：将测试线接于无源待测用户线上，即可振铃用户电话机，据此核实线路的修复情况。

4、 对线对讲功能：用ST220（称甲方）和任意查线机（称乙方）可通过对讲完成对线工作。

5、 直流高压保护及高压验电功能。

6.特制测试大夹子，6P标准接口

技术指标

1、 绝缘测试阻值0-10MΩ分四档指示。

2、 振铃呼叫距离：≤1KM。

3、 断线分辨距离：≤3KM。

4、 感应验电距离:220V≥0.1m;10KV≥4m；35KV≥8m

5、 拨号指标符合GB/T15279-2002要求。

6、 直流保护电压：60V-300V。

6、 电源：普通9V层叠电池。

7、 体积：146mmх54mmх37mm.

8、 重量：≤220g. 

ST220 Telephone line checker

It is on the basis of the ordinary telephones, added the functions of testing obstacles, independent ringing, calling users on the line,High-pressure remind , and high-voltage protection functions. Effectively reduce the workload of line maintenance personnel. With ruggedness it is an ideal business tool for maintenance personnel to open and maintain the related businesses.

Functions introduction:

Telephone function: The same as ordinary telephones, it acquires dial-up call, or bell functions once connect with ordinary telephone lines.

Barriers testing functions: connect the testing line and the users’ line, insulation tests, and gas testing and line broken testing can be carried out.

Call users and Talkback: once connect the testing line and the users’ line, and call users’ telephone, which can verify the restoration lines.

Talkback functions: connect ST220 (Part A) with any Check Machine（Part B）can complete line connection through talkback.

DC high voltage protection,ACHigh-pressure remind

Specifications:

Insulation testing resistance value of 0-10MΩ at 4th grade instructions

Call distance:≤1 km

Disconnection distinguish distance: ≤ 3 km

Dial indicators meet GB/T15279-2002

DC protection voltage: 60v-300v

Power supply: 9 V ordinary batteries

Dimension (mm): 146×54×37

Weight: ≦220g