Transfer Switch
Caterpillar Transfer Switches are used in order to provide a continuous source of power for lighting and other critical loads. The transfer switch will transfer power from the normal power source to an emergency power source. The transfer of power will take place when the voltage from the normal source falls below a preset limit.
A microprocessor is used in order to monitor voltage. Also, the microprocessor is used to control the system. The microprocessor is located on the cabinet door. The microprocessor will provide accurate control of the transfer switch.
All Caterpillar Transfer Switches are designed for use on emergency systems or standby systems. The transfer switches are also rated for total system loads.
This manual provides information on the installation, operation, and maintenance of the switch. A manual is supplied with each transfer switch. The manual details the features of the switch. The manual should be kept in a readily accessible location in order to provide complete reference information about the transfer switch.
Controller
The MX100 controller has three different appearances for the three types of transfer switches: the CTG, the CTG with the A6 option and the CTGD.
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| Illustration 1 | g00834335 |
Illustration 1 shows the back of the MX100 controller for the CTG model.
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| Illustration 2 | g00834286 |
Illustration 2 shows the front of the MX100 controller for the CTG model.
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| Illustration 3 | g00834342 |
Illustration 3 shows the back of the MX100 controller for the CTG model with the A6 option.
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| Illustration 4 | g00834293 |
Illustration 4 shows the front of the MX100 controller for the CTG model with the A6 option.
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| Illustration 5 | g00834345 |
Illustration 5 shows the back of the MX100 controller for the CTGD model.
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| Illustration 6 | g00834295 |
Illustration 6 shows the front of the MX100 controller for the CTGD model.
The MX100 Controller consists of two major assemblies: a microprocessor and a relay transformer box.
The microprocessor contains the System I/O Interface.
The System I/O Interface is located on the left hand side of the back of the unit (1). The System I/O Interface has the following accessories:
- The output of the engine start relay
- The outputs of the source relays
- Timer that determines the amount of time before transfer
- Pre-signal contact in either direction
- Input that inhibits the transfer to emergency power
- Input that inhibits the transfer to normal power
- Input for Remote Peak test
- Input to transfer off EMERGENCY to dead NORMAL
- the network interface card
The relay transformer box (R/T box) contains the relays that are used in order to energize the transfer mechanism of the transfer switch. The R/T box also contains the transformers that are used to drop the line voltage to a control level for the controller input.