User Guide

RTH100 Series Temperature & Humidity Recorder
Instruction Manual
Page 5
5
Access to Instrument
To open the instrument door press the plunger of the door lock and pull the door forward from the right. As the door is opened the
pen lifter raises the pen ( or pens) away from the chart. Remove the thread that secures the pens to the pen lifter for transit pur-
poses.
To make electrical connections and to set contacts remove the chart plate by loosening the three retaining screws and carefully lift
out the chart plate via the finger hole ( care is necessary to avoid pen lifter interference with pens and control pointers ). Pull the
bottom edge clear of the instrument and lower the chart plate from behind the pens. If the instrument already has a chart fitted this
will need to be removed ( see Fig. 4.).
Electrical Connections
BEFORE MAKING ANY CONNECTIONS TO THE INSTRUMENT ENSURE MAINS SUPPLY CABLE HAS
BEEN ISOLATED FROM THE MAINS SUPPLY
All electrical connections are made to terminal blocks in the lower part of the case behind the chart plate.
Mains Supply and Relay Connections
Insert mains supply cable (isolated) through cable gland in the underside of the case and connect to either the stand alone termi-
nal block for recorders or the power supply board terminal block for controllers. A three core cable switched and fused 5 Amp should
be used. Set the voltage selector switch ( adjacent to the transformer) to the required voltage.
Insert relay connection cables through cable glands and connect to relay board terminals, having first removed the relay cover see
Fig. 3.
RELAY CONNECTING CABLES SHOULD ONLY BE CONNECTED AFTER CONTACT DIFFERENTIAL
SETTINGS HAVE BEEN CARRIED OUT ( See page 6.).
Fig 3. Mains Supply & Relay Connections