MS Electronics E914 Product Manual

Product Guide

E914

today, tomorrow and in the future

mselectronics.co.uk

Robust Humidistat
with semi-automatic on/off control

energy saving controls

2

Issue 2.0

Product Overview

The E914 offers a calibration-free, high quality solution to tamperproof humidity control. It utilises
a high-accuracy humidity sensor in conjunction with its robust die-cast aluminium case and
tamperproof screws to ensure vandal-resistant yet accurate tamperproof energy control.

The E914 regulates to a fully adjustable relative humidity set-point between 5% RH and 95% RH,
combined with an adjustable relative humidity hysteresis (differential) of anything between 1% RH
and 10% RH.

The E914’s integrated pushbutton allows the room user to switch off the unit. Humidity control will
automatically be restored after the “Off Timeout” period has elapsed. LED indicators illuminate to
display the state of the humidistat (Green = ON (humidity control enabled) or Red = OFF (humidity
control disabled)).

Product Wiring

1. IMPORTANT: ensure all electrical connections are isolated before commencing any work on the

unit.

2. Power to the humidistat is provided via the Live and Neutral input terminals labelled “L” and “N”
(230V AC, 50Hz). This supply should be suitably fused.

3. NOTE: This humidistat MUST be earthed using the earth terminal provided.

4. A voltage-free changeover relay output capable of switching loads of up to 16A, 250V AC
(resistive) is provided by the humidistat. Connect to your application in an appropriate manner
given the following:

• If the sensed humidity is higher than the setpoint humidity:
The Common “COM” terminal is connected to the Normally Open “N/O” terminal.
(The Normally Closed “N/C” terminal is disconnected).

• If the sensed humidity is lower than the setpoint humidity, or the OFF mode is selected:
The Common “COM” terminal is connected to the Normally Closed “N/C” terminal.
(The Normally Open “N/O” terminal is disconnected).

Figure 1 Typical wiring example