Control Timer Ema 194-196
Control Timer Ema 194-196
Control Timer Ema 194-196
APPLICATION
The EMA 194 and EMA 196 control timers are used as control and checking devices for the
systems of central lubrication fitted with progressive distributors and lubrication pumps ACF.
The lubricating circuits may be fitted with snap-action and contact-less switches. Their basic
versions are used in central lubrication systems of mobile machines and devices, principally
chassis of buses, trucks and lorries, trolley-buses, building and earthwork machines,
agricultural and forest equipment.
When adaptated for 230/400V voltages, control timers may be applied to the circuits of
central lubrication fitted with progressive distributors and arbitrary electrically driven
lubricating devices, such as, for instance UCF, VEG, 12T1.
DESCRIPTION
The control timer is an electronic circuit made of integrated circuits, passive elements,
control, checking, and connecting elements on a printed circuit board. It is connected to the
fuse box with a connector. Mechanically it is attached with screws to the standardised box
made of a cured plastic. The front panel of the control unit carries change-over switches for
setting the period of time indicated by “CONTROL“ (EMA 194) or “OPERATION“ (EMA 196)
labels and for setting the pause interval between the individual lubricating cycles indicated by
the “PAUSE“ label. In the middle, there is a “CONTROL RESET - PRELUBRICATION“
button. Below this button, a green (LED diode) “IGNITION ON“ telltale lamp, in the middle, a
red (LED diode) “FAILURE“ (EMA 194) telltale lamp, and a green (LED diode)
“OPERATION“ telltale lamp are installed. Below them, the wiring diagram of the supply
connector is drawn. Standard delivery includes a connecting cable of 2m length.
The control timer is fitted with a microcomputer fitted with integrated memory independent
from the supply voltage of the source. It is a crystal-controlled device and this permits a high
degree of accuracy of the time intervals. The power circuits provide for protection against
short circuits at the output (motor, bulb). The inlet 30 (+) is protected against voltage peaks
by two LC-filters, a varistor and a transil; the inlet L (inductive. sensor), with a Z-diode and a
transil; the inlet 15 (key) with a Z-diode, LC filter, varistor, and a transil. The whole unit –
including the power switches - is furnished with protection against pole reversal.
OPERATION
EMA 194
When an operating voltage of +12V (+24V) is supplied to connection 30 and to connection 31
(the frame), the control timer is put into operation.
Supply of the voltage to terminal 15 (starter switching-on) puts the device into operation and
it continues the cycle from the point where it was when the starter was last switched off. At
the same time, the telltale “IGNITION ON“ lamp switches on. In the case where the previous
operation had been interrupted in the “PAUSE“ status, the counting of the time to the value
set with the “PAUSE“ changeover switch will be completed. The voltage is supplied to
terminal M and this puts the lubrication pump into operation. Then the “OPERATION“ telltale
lamp switches on. When the lubricating cycle, indicated by the signalling on the progressive
distributor to the terminal P ends, the operation of the lubrication pump is stopped and the
“PAUSE“ time starts to be counted again.
- “PAUSE“ set 0
“CONTROL“ set 0
The lubrication pump keeps operating regardless of the signal from the progressive
distributor.
- “PAUSE“ set 0
“CONTROL“ any setting except for 0
After the signal of the cycle conclusion from the progressive distributor, the lubrication
pump immediately initiates the next lubricating cycle.
- “PAUSE“ any setting except for 0
“CONTROL“ set 0
The lubrication pump is not able to initiate the lubricating cycle. Lubrication does not take
place.
The EMA 194 control timer is intended to control a lubrication pump provided with continuous
supply of lubricant (for instance the electrically driven ACF). For controlling the cyclic
operation of a lubrication pump (for instance the pneumatically driven ANC 20P) the EMA
194/S control timer is supplied. In this case, the lubrication cycle takes place in such a
manner that the electromagnetic distributor, governed by the control unit, supplies air to the
unit’s pneumatic cylinder for several seconds, then for several seconds the supply of air is
interrupted so that the unit piston returns. This cycle repeats until the signal from the limit or
induction switch, reporting the end of a lubricating cycle, is received.
EMA 196
When an operating voltage of +12V (+24V) is supplied to connection 30 and to connection 31
(the frame) the control timer is put into operation.
Supply of voltage to terminal 15 (starter switching-on) puts the device into operation and it re-
establishes the operation at the point of the cycle where it was interrupted when the starter
was last switched off. At the same time, the “IGNITION ON“ telltale lamp on the timer
switches ON. In the case where the previous operation had been interrupted in the “PAUSE“
status, the counting of the time to the value set with the “PAUSE“ changeover switch will be
- “PAUSE“ set 0
“OPERATION“ any setting except for 0
Lubrication pump operating continuously.
- “PAUSE“ any setting except for 0
“OPERATION“ set 0
The lubrication pump is not able to initiate the lubricating cycle. Lubrication does not
take place.