Kohler 20--2800 kW manual Automatic Transfer Switches, Control Connections, Remote Annunciator

7.5 Automatic Transfer Switches

A typical standby system has at least one automatic transfer switch connected to the generator set output to automatically transfer the electrical load to the generator set if the normal source fails. When normal power returns, the switch transfers the load back to the normal power source and then signals the generator set to stop.

The transfer switch uses a set of contacts to signal the engine/generator to start. These contacts are terminals 3 and 4 on the generator set controller terminal strip or controller connection terminal strip (if used) inside the junction box. When the normal source fails and the generator set master switch is in the AUTO position, the transfer switch contacts close to start the generator set.

The location of the transfer switch contacts is usually near the contactor with an engine start decal to identify the correct terminals. The terminals are identified as 3 and 4 (or 57 and 58). Do not connect to terminals 57 and 58 on the inner panel circuit board. Connection must be at the contactor location. Verify the correct engine start terminals using the transfer switch wiring diagrams before making connections.

7.6 Control Connections

Most standby generators can be equipped with a myriad of optional equipment that will have to be connected to other components in the system. These accessories will enable the generator set to meet standards for local and national codes, or specific requirements of the customer’s installation. A few of the more common accessories and their functions are listed on the following pages.

7.7 Remote Annunciator

The remote annunciator allows monitoring of the standby power system from a location remote from the generator set. Individual lamps identifying fault shutdowns and/or prealarms are located on the remote annunciator, along with an alarm horn and silence switch. There are both surface- and flush-mount models available. The remote annunciator is typically located in an area that is monitored on a full-time basis. This allows the operator to be aware of any alarm conditions when they occur without having to be physically present at the generator set. See Figure 7-6.

Remote Annunciator

A-258782

14-Relay Dry Contact Box

42A

2

K1

K2

K3

K4

K5

K6

K7

K8

K9

K10 K11 K12 K13 K14

INPUT

CONTACT RATINGS: 10A @120VAC RESPCB. LOADASSY A-320639

.01A @28VDC MIN.

LOT NO.

10A @28VDC MAX.

NO C NO

C NO

C NO C

NO C NO C NO

C NO C

NO C

NO C

NO C NO C NO C

K1

K2

K3

K4

K5

K6

K7

K8

NOK9C K10

K11

K12 K13

K14

N

42B

P

P

FBA-1 10 AMP

A-293983

Figure 7-6 Remote Annunciator with 14-Relay Dry Contact Kit

7.8 Audiovisual Alarm

The audiovisual alarm warns the operator of a fault shutdown or prealarm condition at a remote location. See Figure 7-7.

Front View Side View

A-292887

Figure 7-7 Audiovisual Alarm

38 Section 7 Electrical Requirements TP-5700 7/93