Checking The Function Of The Relays - Stiga e-PARK 220 Workshop Manual

WORKSHOP MANUAL
e-PARK 220

8.4.3 Checking the function of the relays

A basic relay consists of a coil of wire wound around a soft iron (magnetic) core. When current is
passed through the coil, the core is magnetized and pulls down on a magnetic lever.
The lever in turn is attached to several switch contacts which open or close other electrical circuits.
In this fashion, a small current can control one or more larger electrical currents and actuate sev-
eral other devices.
In most cases a relay contact moves only a fraction of an inch and the magnetic pull is low.
To check the operation of a relay you must have an Ohmmeter-dependent tester.
Disconnect the relay and connect the tester tips to the various contacts of the component con-
cerned, an initial check with the relay disconnected and another with the power supply contacts
connected to an external 12 Volt battery.
The readings shall be as indicated in the table below, where the red continuous line indicates the
electrical continuity occurring inside.
KS
KZTP
KM
KT
OPC
BLADE
CLUTCH
TEMP
Definitions
CHAPTER
8 - ELECTRICAL SYSTEM
Condition
Not powered
86
Powered
30
87A 87
85
EDITION
2018
Diagram Readings
86 86
87A-30 = 0
87-30 = ∞
30 30
87A 87 87A
85 85
86
87A-30 = ∞
87-30 = 0
30
87A 87
85
PAGE
56 /
84
87